2018 Honda Accord Press Kit - Powertrain

Oct 1, 2017

The 10th generation 2018 Accord takes an entirely new approach to performance with its two new direct-injected VTEC Turbo® 4-cylinder engines with dual VTC – a 1.5-liter 16-valve inline-4 and a 2.0-liter 16-valve DOHC inline-4. Both new turbocharged engines produce peak torque across a broad range of engine speed (RPM), delivering smooth and virtually lag-free power for exceptional throttle response and power delivery in all driving conditions.

The 1.5-liter turbo is mated to a Honda continuously variable automatic transmission (CVT) with G-Shift Control or, in Sport trim, to either a CVT or a short-throw 6-speed manual transmission (6MT). The new 2.0-liter turbo, sharing much of its design with the 2017 Civic Type-R engine, can be mated to a smooth, responsive Honda-designed 10-speed automatic, the first of its kind for a front-wheel-drive car, or, in Sport trim, to the 10AT or a short-throw 6-speed manual.

New 2.0L DOHC VTEC Turbo Engine with New 10-speed Automatic Transmission

The two new automatic transmissions take greater advantage of available torque while maximizing quietness and efficiency during highway cruising. The redesigned CVT has an 11-percent lower ratio compared to the previous generation version for more powerful launch performance, while the new 10AT is 22 lbs. lighter, with a 43-percent lower first gear and a 17-percent taller top gear compared to the previous generation Accord's 6-speed automatic.

The new gas-engine powertrains are joined by the third generation of Honda's Intelligent Multi-Mode Drive (iMMD) two-motor hybrid technology. The new hybrid powertrain features a 2.0-liter Atkinson-cycle engine with improved thermal efficiently, now at 40 percent (up from 38.9 percent on the 2017 Accord Hybrid), the highest for any mass-produced Honda engine. The engine is paired with two Honda-developed electric motors that are the first drive motors in the world to use permanent magnets containing no heavy rare-earth metals. As before, the Accord two-motor system operates without the need for a conventional automatic transmission.

Additionally, a new, more compact intelligent power unit (IPU) containing the hybrid battery pack and its control systems is now mounted under the rear floor instead of in the trunk. This packaging provides the same 16.7 cu. ft. of trunk space as its gasoline-only counterpart, and preserves the flexibility and utility of a 60/40-split and folding rear seat, standard on the Accord Hybrid EX and above trims.

Key Powertrain Features

Engines

New VTEC Turbo® 1.5-liter, DOHC direct-injected inline-4 engine*

192 horsepower at 5500 rpm (SAE net)
192 lb.-ft. torque at 1,600-5,000 rpm (SAE net)
Dual VTC and VTEC® valvetrain
Low inertia Mono-scroll turbo system with electric wastegate
Computer-controlled Direct Injection (DI) with multi-hole fuel injectors
10.3:1 compression ratio
Lightweight, high rigidity steel crankshaft
"4-into-2" exhaust manifold
Sodium-filled exhaust valves
Forged steel connecting rods
Drive-by-Wire™ throttle system
Maintenance Minder™ system optimizes service intervals
100,000 +/- miles tune-up interval
Regular Unleaded fuel recommended

New VTEC Turbo® 2.0-liter, DOHC direct-injected inline-4 engine*

252 horsepower at 6,500 rpm (SAE net)
273 lb.-ft. torque at 1,500-4000 rpm (SAE net)
Dual VTC and VTEC valvetrain
Low inertia mono-scroll turbo system with electric wastegate
Computer-controlled Direct Injection (DI) with high-flow fuel injectors
9.8:1 compression ratio
Super lightweight, high rigidity steel crankshaft
"4-into-1" exhaust manifold integrated into cylinder head casting
Sodium-filled exhaust valves
Forged steel connecting rods
Drive-by-Wire™ throttle system
Maintenance Minder™ system optimizes service intervals
100,000 +/- miles tune-up interval
Regular Unleaded fuel recommended

Two-Motor Intelligent Multi-Mode Drive (i-MMD) Hybrid powertrain

2.0-liter, DOHC, i-VTEC® Atkinson-cycle inline-4 engine
Engine output: 143 horsepower at 6200 rpm
Engine output: 129 lb.-ft. torque at 3500 rpm
i-VTEC® (Variable Valve Timing and Lift Electronic Control) + Electric VTC
Computer-controlled port fuel injection with multi-hole fuel injectors
13.5:1 compression ratio
Drive-by-Wire™ Throttle System
Maintenance Minder™ system optimizes service intervals
100,000+/- miles engine tune-up interval
Regular Unleaded fuel recommended
Electric motor output: 181 peak horsepower at 5,000 to 6,000 rpm
Total system horsepower: 212
Eight-year/100,000-mile or ten-year/150,000-mile Li-Ion battery limited warranty, depending on the state of purchase/registration

Emissions/Fuel Economy Ratings

Emissions Ratings
- 1.5-liter turbo: LEV3-ULEV50; LEV3-SULEV30
- 2.0-liter turbo: LEV3-ULEV50; LEV3-SULEV30
- Hybrid: LEV3-SULEV30
EPA fuel-economy ratings (city/highway/combined)
- 1.5-liter turbo with 6MT (Sport trim): 26/35/30 mpg¹
- 1.5-liter turbo with CVT (LX, EX & EX-L Trims): 30/38/33 mpg¹
- 1.5-liter turbo with CVT (Sport & Touring trims): 29/35/31¹
Anticipated EPA Fuel Economy Ratings (city/highway – targets only, not final)
2.0-liter turbo with 6MT(Sport trim): 22/32 mpg
2.0-liter turbo with 10AT (EX-L trim): 23/34 mpg
2.0-liter turbo with 10AT (Sport & Touring trims): 22/32 mpg
2.0-liter Hybrid: TBA

¹ Based on 2018 EPA fuel-economy ratings. Use for comparison purposes only. Your mileage will vary depending on how you drive and maintain your vehicle, battery pack age/condition (Hybrid only), driving conditions and other factors.

Transmissions

6-speed Manual (1.5-liter and 2.0-liter Accord Sport)
Continuously Variable Transmission (Accord 1.5-liter turbo)
New 10-speed automatic (Accord 2.0 turbo)

Engine Architecture and Features

Turbocharged 1.5-Liter In-Line 4 Cylinder
The new DOHC 1.5-liter engine in the Accord is a further evolution of the powerplant first introduced in the 2016 Civic and later applied to the 2017 CR-V. With direct injection, a low-inertia Mono scroll turbo with electric waste-gate and dual Variable Timing Control (VTC), the turbocharged powerplant delivers more horsepower and torque than before.

Power output is increased in part by a new "4-into-2" exhaust manifold that improves the flow of exhaust gas to the turbo (see below). Peak output of 192 horsepower (hp) at 5,500 rpm and 192 lb.-ft. of torque from 1,600 to 5,000, compared to 185 hp at 6,400 rpm and 181 lb.-ft. at 3,900 rpm on the previous Accord's normally aspirated 2.4-liter engine.

The Accord 1.5-liter turbo is rated by the EPA at 30/38/33 mpg¹ when equipped with the available CVT transmission (except Sport trim), and 26/35/30 mpg¹ city/highway/combined when equipped with the standard 6-speed manual transmission, improvements of up to 3/2/3 mpg for the CVT, and 3/3/4 mpg for the 6MT, depending on trim.

¹ Based on 2018 EPA fuel-economy ratings. Use for comparison purposes only. Your mileage will vary depending on how you drive and maintain your vehicle, driving conditions and other factors.

Cylinder Head and Valvetrain
The direct-injected 1.5-liter 4-cylinder turbocharged engine has a lightweight, low-pressure die-cast aluminum alloy cylinder head with exhaust manifold cast directly into the cylinder head, eliminating the need for a separate exhaust manifold. For improved fuel efficiency and responsiveness, the manifold has a "4-into-2" design; the engine's eight exhaust valves are grouped in two sets of four, each group with a separate exhaust manifold and exit port to the turbocharger cast into the cylinder head, which helps smooth exhaust flow to the turbocharger for more efficient operation and better low-rpm response.

A low-friction, silent-chain drives dual overhead cams and four valves per cylinder. The cam drive is maintenance free throughout the life of the engine. To help further reduce weight, new thin-wall hollow camshafts are used.

To benefit fuel efficiency, emissions and power, the turbo engine utilizes sodium filled exhaust valves. A hollow chamber within the valve contains sodium that is cooled by the exhaust port cooling jacket. Since the chamber reaches close to the valve head, the sodium helps to cool the entire valve. Since the valve is internally cooled, it doesn't need the enriched fuel mixture that was generally used in turbo engines to help cool the exhaust valve. The resultant leaner mixture reduces emissions, increases fuel efficiency and helps increase power.

The cylinder head includes small 12-millimeter (M12) sparkplugs, down from the more common 14-millimeter (M14) size, to save space and weight. The head also includes direct-injection multi-hole fuel injectors with a small diameter bore. Higher-pressure direct injection optimizes fuel atomization, allowing for more efficient combustion. To provide a high-tumble intake charge that further enhances combustion efficiency, both the intake port and piston crown have special designs.

The 1.5-liter DOHC 16-valve VTEC Turbo engine uses an advanced valve control system to combine high power output with high fuel efficiency and low emissions. The system combines intake and exhaust Variable Timing Control (dual VTC), which continuously adjusts the intake and exhaust camshaft phase, with Variable Valve Timing and Lift Electronic Control (VTEC), which changes valve lift, timing and duration of the exhaust valves. In this application, the increased valve lift from VTEC operation varies to improve gas scavenging at low speed, part throttle conditions, as well as higher speed, full throttle operation, helping to improve performance across the engine speed range.

The cam timing is varied based on input from sensors that monitor rpm, timing, throttle opening, cam position and exhaust air-fuel ratio. The result is increased fuel efficiency and lower emissions.

Turbocharged 2.0-Liter In-Line 4 Cylinder
Assembled in Honda's Anna, Ohio engine plant using domestic and globally-sourced parts, the Accord's available DOHC 2.0-liter engine shares much of its design with the race-bred 2017 Civic Type R and has the highest torque ever offered in an Accord. Compared to the 2.0-liter turbo in the Civic Type R, the Accord's 2.0-liter engine uses a turbocharger with a smaller, low-inertia turbine for improved low-rpm boost response. With a maximum of 20.8 psi of boost, the Accord's 2.0-liter powerplant peak output is 252 hp (SAE net) at 6,500 rpm and 273 lb.-ft. of torque (SAE net) from 1,500 to 4,000 rpm.

With 33-percent greater displacement than the Accord's standard 1.5-liter turbocharged engine, the 2.0-liter powerplant delivers a maximum increase of 60 horsepower and 81 lb.-ft. of torque. Compared to the 3.5-liter normally aspirated V6 it replaces, the 2.0-liter engine has less peak horsepower (252 vs. 278) but greater peak torque (273 lb.-ft. of torque from 1,500 to 4,000 rpm, vs. 252 lb.-ft. at 4,900 rpm). With peak torque available at a much lower engine rpm, responsiveness and acceleration are notably enhanced. The 2.0-liter turbo also offers much broader power delivery, holding a torque advantage over the V6 that spans the entire operating range between 1200 and 4800 rpm – the engine rpm range that is typically used the most.

The turbocharged Accord 2.0-liter turbo is designed to operate on Regular unleaded fuel. EPA fuel economy ratings are pending at this writing.

Cylinder Head and Valvetrain
The direct-injected Accord 2.0-liter 4-cylinder VTEC Turbo engine has a lightweight, low-pressure die-cast aluminum alloy DOHC cylinder head. With exhaust ports cast directly into the cylinder head, the use of a separate exhaust manifold is eliminated, reducing engine weight and simplifying assembly. The manifold is also liquid cooled to help keep heat in check and has a "4-into-1" design for improved fuel efficiency and responsiveness.

A low-friction, silent chain drives dual overhead cams and four valves per cylinder. The cam drive is maintenance free for the life of the engine. To further reduce weight, thin-wall hollow camshafts are used.

To benefit fuel efficiency, emissions and power, the turbo engine utilizes sodium-filled exhaust valves. A hollow chamber within the valve contains sodium that is cooled by the exhaust port cooling jacket. Since the chamber is close to the valve head, the sodium helps to cool the entire valve; and since the valve is internally cooled, it doesn't need the enriched fuel mixture that is generally used in turbo engines to help cool exhaust valves. The resultant leaner mixture reduces emissions increases fuel efficiency and increases power.

The Accord's 2.0-liter DOHC 16-valve VTEC Turbo engine uses an advanced valve control system to combine high power output with high fuel efficiency and low emissions. The system combines intake and exhaust Variable Timing Control (dual VTC), which continuously adjusts the intake and exhaust camshaft phase, with Variable Valve Timing and Lift Electronic Control (VTEC), which changes valve lift, timing and duration of the exhaust valves.

The cam timing is varied based on input from sensors that monitor rpm, timing, throttle opening, cam position and exhaust air-fuel ratio. The result is increased fuel efficiency and lower emissions.

The cylinder head includes small 12-millimeter (M12) sparkplugs, down from the more common 14-millimeter (M14) size, to save space and weight. The head also includes direct-injection multi-hole wide-range fuel injectors with a small-diameter bore. Higher-pressure direct injection optimizes fuel atomization, allowing for more efficient combustion. To provide a high-tumble intake charge that further enhances combustion efficiency, both the intake port and piston crown have special designs.

High-Flow Exhaust System
The Accord 2.0-liter engine features a specially designed high-flow exhaust system with a large-diameter central pipe with resonator that splits into dual exhaust silencers and dual outlets. The system is engineered to offer a distinctive exhaust note under acceleration, coupled with quiet cruising at low power settings.

Common Turbocharged Engine Features

Dual Variable Timing Control (Dual VTC)
Dual VTC adjusts cam timing for optimal balance of power and efficiency. Based on a range of sensor information, VTC adjusts an oil control valve which acts as a hydraulic actuator that can vary the position of each camshaft sprocket relative to the cam it drives. Under light loads, valve overlap can be increased to reduce pumping losses and improve fuel efficiency. When engine speed is low and engine load is large, such as during initial acceleration, the amount of overlap is increased to boost the scavenging effect, which improves torque and responsiveness. When engine speed is high and engine load is also high, such as during full-throttle acceleration, the amount of valve overlap is reduced to increase engine output by improving both intake and scavenging.

Cylinder Block and Crankshaft
The Accord's turbocharged inline 4-cylinder engines have a lightweight die-cast aluminum block with reinforced main bearing caps to minimize weight. Centrifugally cast iron cylinder sleeves provide long-lasting durability. Each journal on the crankshaft is micropolished to reduce operating friction.

Pistons and Connecting Rods
The Accord's turbocharged engines have pistons with "cavity-shaped" crowns that help maintain stable combustion and contribute to improved efficiency. The lightweight pistons have a carefully optimized skirt design to minimize reciprocating weight, which minimizes vibration and increases operating efficiency. The pistons are cooled by oil jets directed at the underside of each piston crown. Special cooling channels in the pistons also help keep operating temperatures in check. Ion-plated piston rings help reduce friction for greater operating efficiency. Lightweight, high-strength steel connecting rods are heat-forged in one piece and then "crack separated" to create a lighter and stronger rod with an optimally fitted bearing cap.

ECON and SPORT Modes
Every 2018 Accord is equipped with a green ECON button located on the center console near the shift lever. When the button is pushed to activate ECON mode, several operating characteristics of the vehicle are modified for enhanced fuel efficiency. The Drive-by-Wire™ throttle system provides more gradual response, and to save additional energy, the climate control's fan speeds are lowered incrementally and other climate control system characteristics are altered based on the conditions. Another push of the ECON button reverts all systems to their normal mode.

Touring trims of the Accord 1.5 and 2.0-liter models are available with SPORT mode, which is selectable via a button on the center console. SPORT mode alters a range of chassis features, including suspension dampers, steering assist level, Agile Handling Assist, as well as powertrain features, including Drive By Wire, shift mapping (with automatic transmission), and Active Sound Control (ASC). With SPORT mode selected, the Accord takes on a more aggressive, fun-to-drive edge (see Chassis section for additional detail).

Direct Injection System
Both turbocharged powerplants feature a direct-injection system that enables increased torque across the engine's full operating range along with higher fuel efficiency. The system features a compact, high-pressure, direct-injection pump that allows both high fuel flow and pulsation suppression, while variable pressure control optimizes injector operation. Multi-hole injectors deliver fuel directly into each cylinder (not to the intake port, as in conventional port fuel injection designs), allowing for more efficient combustion.

The multi-hole injectors help create the ideal stoichiometric fuel/air mixture in the cylinders for good emissions control. Theoretically, a stoichiometric mixture has just enough air to completely burn the available fuel. Based on the operating conditions, the direct-injection system alters its function for best performance. Upon cold engine startup, fuel is injected into the cylinders on the compression stroke. This creates a weak stratified charge effect that improves engine start-up and reduces exhaust emissions before a normal operating temperature is reached.

Once the engine is fully warmed up, for maximum power and fuel efficiency fuel is injected during the intake stroke. This helps create a more homogeneous fuel/air mix in the cylinder that is aided by the high-tumble intake port design. This improves volumetric efficiency, and the cooling effect of the incoming fuel improves anti-knock performance.

Low Inertia Mono Scroll Turbo System with Electric Wastegate
Both turbocharged Accord powerplants feature mono scroll IHI turbochargers with small-diameter, low-inertia turbines for maximum responsiveness. The mono scroll housing design helps the turbo build boost even at relatively small throttle openings and low engine rpm. The electrically actuated wastegate allows boost pressure to be precisely controlled.

A large air low-restriction intercooler is positioned low in the front of the car where it receives unobstructed airflow when the vehicle is in motion. The intercooler helps reduce the temperature of air entering the engine, increasing its density for greater performance. Intake air travels from the air filter, to the turbo compressor, on to the intercooler, then to the engine's intake ports. To reduce weight, the turbo system is plumbed with rigid, lightweight resin composite inlet pipes to carry intake air to and from the intercooler.

Advanced Transmissions

6-Speed Manual Transmission
Accord Sport models offer available 6-speed manual transmissions (6MT) with either the 1.5-liter or 2.0-liter turbocharged engines. The two manual transmissions are engineered to match the displacement and torque output of the engine they are paired with. Both units offer smooth and precise shift feel and great efficiency, making them the perfect complement to the Accord's sporting side. A constant-mesh helical reverse gear mechanism significantly reduces noise when reverse is used. A reverse lockout feature prevents the transmission from accidentally being shifted into reverse while the car is moving forward.

Continuously Variable Transmission (CVT)
Accord 1.5-liter offers the responsiveness and efficiency of an available Continuously Variable Transmission (CVT). The Continuously Variable Transmission (CVT) has smooth and predictable gear ratio transitions and excellent acceleration matched with efficient low-rpm cruising. A wide ratio spread results in strong acceleration performance coupled with reduced engine rpm at high road speeds. The redesigned CVT has an 11-percent lower ratio compared to the previous-generation version for more powerful launch performance.

G-Design Shift Feature
The Accord CVT is designed to provide the optimum gear ratio for the driving conditions, and to offer a more natural driving feel than some previous CVT transmissions that may have something of a disconnected "rubber-band" feel compared to a conventional automatic transmission.

The Accord CVT has a special G-design shift logic that is designed to offer more immediate acceleration response than other CVT designs. When abruptly applying power from a steady-state cruising speed, the CVT immediately sends power to the drive wheels while simultaneously adjusting the gear ratio (seamlessly and progressively downshifting) to smoothly bring the engine to its horsepower peak in a linear way.

During full throttle acceleration, G-Design shift logic employs stepped ratios as the vehicle speed increases. This helps give the transmission a more "connected" feel as the engine rpm and vehicle speed increase together. This stepped operation also improves acceleration performance incrementally.

CVT Automatic Modes
The transmission can be operated in three different fully automatic forward modes with the console-mounted straight-gate shifter. The D mode is ideal for most driving situations, and combines fuel efficiency with smooth operation and responsive power when needed. The S mode is for more performance-oriented driving and features more aggressive transmission mapping to keep engine rpm higher for greater acceleration and response, while also providing greater engine braking. The L mode is ideal for situations when additional engine braking is desired, such as in mountainous driving.

10-Speed Automatic Transmission (10AT)
Accord 2.0-liter models are available with a new, Honda-developed 10-speed automatic transmission (10AT), the first of its kind in the Accord's segment. Engineered for high efficiency with low internal inertia and an exceptionally wide ratio range, the 10AT maximizes the Accord's performance and fuel efficiency. Compared to the previous 6-speed automatic, the 10AT is 22 lbs. lighter and has a 68 percent wider overall ratio range with a 43 percent lower first gear and a 17 percent taller top gear.

The 10AT is designed to be lightweight and compact. It features four planetary gear sets that work together to provide an exceptionally wide ratio spread of 10.139:1 compared to 6.041:1 on the previous-generation Accord's 6-speed unit. The 10-speed also has substantially faster upshift and downshift performance than the previous generation 6-speed transmission. For greater responsiveness, the 10-speed transmission can make 4-gear direct downshifts: from 10th to 6th, or from 7th to 3rd.

To maximize fuel efficiency and minimize interior noise, the transmission's 10th gear is exceptionally tall, resulting in quiet and relaxed cruising rpm.

Shift-By-Wire Gear Selector
In the 2018 Accord with 10-speed automatic transmission, the conventional shift lever is replaced with a fully electronic, shift-by-wire gear selector. Park, Neutral and Drive are selected with the push of a button. Reverse is selected by pulling back a dedicated switch. Indicator lights on or next to the buttons indicate the mode selected. As an added safety feature, if the vehicle is brought to a stop in Drive or Reverse, the system will automatically select Park if the driver's seatbelt is unbuckled and the driver's door is opened. A steering wheel-mounted paddle shifter system lets the driver take manual control of transmission gear selection.

Common CVT/10AT Transmission Features

Automatic Modes
Both the Accord CVT and 10-speed automatic transmissions can be operated in two different fully automatic modes. The D (or "Drive") mode is ideal for most driving situations, and combines fuel efficiency with smooth operation and responsive power when needed. The CVT's S mode and the 10AT SPORT mode are meant for more demanding driving, and feature more aggressive shift mapping to keep engine rpm higher for greater acceleration and pulling power.

When in the D mode (optimized for normal driving), the transmission incorporates an advanced Grade Logic Control System, Shift Hold Control and Cornering G Shift Control – all of which reduce unwanted shifting and gear hunting. The result is smart transmission operation that optimizes fuel efficiency and keeps the transmission in the appropriate gear for driving conditions, generating excellent performance and smooth operation.

While ascending or descending hills, Grade Logic Control alters the transmission's shift schedule to reduce shift frequency and improve speed control. The transmission ECU continually measures throttle position, vehicle speed and acceleration/deceleration to determine when the vehicle is on a hill. The shift schedule is then adjusted – during ascents to hold the transmission in lower gears to boost climbing power, and during descents to provide greater engine braking.

Shift Hold Control keeps the transmission in its current (lower) gear ratio during aggressive driving, as in the case of decelerating at a corner entry. Shift Hold Control leaves the chassis undisturbed by eliminating excess shifting and ensures that power will be more immediately available (without a downshift) at the corner exit. Cornering G Shift Control monitors the speed of each rear wheel independently to determine when the Accord is turning. When the system detects a sufficient speed differential between the rear wheels, it will suppress any unwanted upshifts. This prevents the transmission from upshifting during a corner, which could upset the chassis balance thus requiring downshifting again at the corner exit when the throttle is applied.

Paddle Shifters
Touring trims and Sport trims with automatic transmission for both the 1.5- and 2.0-liter engines feature dual steering wheel-mounted paddle shifters. Particularly useful in mountainous terrain or during spirited driving, the paddles give the driver greater control over transmission operation. On long downgrades, the driver can command downshifts with the paddles that allow increased engine braking to reduce the load on the brakes and help control the Accord's downhill speed.

Paddle Shifter Operation in Drive Mode
While in Drive mode, special transmission logic programming allows the use of the steering-wheel-mounted paddle shifters. When the driver operates the paddle shifters, the transmission responds to the driver's shift command and then returns to its normal fully automatic mode if further paddle shift inputs are not made within a few seconds depending upon driving conditions. This special logic makes it easy for the driver to command a quick downshift without leaving the convenience of Drive mode. This temporary manual mode can be cancelled at the driver's will by continued operation of the right-side paddle until the transmission resumes "Drive."

Paddle Shifter Operation in Sequential Mode
By selecting the "S" position with the shifter (CVT) or pressing the SPORT button (10AT), Sequential mode is engaged. This mode offers automatic operation with more aggressive shift mapping. A pull on either of the paddle shifters places the transmission in fully manual mode until another mode of operation is selected. A digital display in the instrument cluster indicates which gear the transmission is in.

In the CVT transmission, a double-kick-down feature lets the driver command a sporty double downshift – such as from fifth to third gear. By pulling on the left downshift paddle twice in rapid succession, the transmission will drop directly to the chosen lower gear ratio. With the 10AT, the Drive-by-Wire™ throttle system also creates a "blip" of the throttle to help match gear speeds while downshifting.

To prevent harm to the powertrain when the transmission is paddle shifted by the driver (including during double-kick-down shifts), the system will inhibit potentially damaging shifts. As an added safety measure, the Electronic Control Unit (ECU) can also cut off fuel to the engine to prevent over-revving. If fuel cutoff is insufficient to prevent engine over-revving, as may be possible when the vehicle is on a steep downhill, the transmission will automatically upshift to prevent damage. On downshifts, the transmission will not execute a driver command that will over-rev the engine.

For improved stop-and-go performance and to help prevent "lugging" the engine, the transmission will automatically downshift to first gear even though the transmission has been left in a higher gear, (except in second gear launch with 10AT) as the vehicle comes to a stop.

Cooperative Control
Both shift performance and smoothness are improved by cooperative control between the Drive-by-Wire™ throttle system and the electronically controlled transmission. The engine is throttled by the engine management system during upshifts and downshifts so the function of the engine and transmission can be closely choreographed for faster, smoother shifting. As a result, the peak g-forces (or "shift shock") are reduced significantly during upshifts and downshifts.

Manual Transmission Gear Ratio Comparison

Gear	2017 Accord 2.4L 6MT	2018 Accord 1.5T 6MT	2018 Accord 2.0T 6MT
1st	3.643	3.643	3.625
2nd	2.080	2.080	2.115
3rd	1.361	1.361	1.529
4th	1.024	1.024	1.125
5th	0.830	0.830	0.848
6th	0.686	0.686	0.686
Reverse	3.673	3.673	3.758
Final Reduction Ratio	4.105	4.105	3.842

Continuously Variable Transmission Gear Ratio Comparison

Gear Ratio (X:1)	2017 Accord 2.4L CVT	2018 Accord 1.5L T CVT
Forward	2.645~0.405	2.645~0.405
Reverse	1.859~1.265	1.859~1.265
Final Reduction Ratio	3.238	3.238

Automatic Transmission Gear Ratio Comparison

Gear	2017 Accord V6 6AT	2018 Accord 2.0T 10AT
1st	3.359	5.340
2nd	2.095	3.329
3rd	1.485	2.224
4th	1.065	1.625
5th	0.754	1.327
6th	0.556	1.018
7th	–	0.796
8th	–	0.665
9th	–	0.591
10th	–	0.527
Reverse	2.269	4.045
Final Reduction Ratio	3.941	3.55

Accord Hybrid

Third-Generation Intelligent Multi-Mode Drive (i-MMD) Two-Motor Hybrid System
The 2018 Accord Hybrid's third-generation i-MMD Two-motor hybrid system is a highly efficient powertrain that selects the optimal drive operation under a wide range of driving conditions to combine fun-to-drive performance with outstanding fuel efficiency. The new hybrid powertrain utilizes a 2.0-liter Atkinson-cycle engine with 40 percent thermal efficiency, up from 38.9-percent in the previous generation Accord Hybrid, and the highest thermal efficiency of any mass-produced Honda engine.

The engine is paired with two electric motors – a propulsion motor and a generator/starter motor. These new motors are the first drive motors in the world to use magnets containing no heavy rare-earth metals, a new Honda-patented design that reduces magnet cost and weight.

Detailed energy management for each component, as controlled by the Power Control Unit (PCU), enables this system to make the best use of both the electric propulsion motor and the gasoline engine to provide seamlessly smooth and responsive performance while garnering top-class EPA fuel economy ratings in the midsize hybrid sedan class.

To help maximize efficiency on the road, the Accord Hybrid seamlessly shifts between three distinct drive operations: EV Drive (100-percent electric motor), Hybrid Drive (electric motor and gasoline engine [driving the generator motor]) and Engine Drive (gasoline engine), utilizing power from the Atkinson-cycle i-VTEC® 4-cylinder engine and the electric motors to suit the driving conditions moment to moment.

EV Drive Operation
All-electric drive EV Drive operation occurs when starting from a stop, during light cruising and acceleration, and when braking. The gasoline engine is off when the i-MMD is in EV Drive mode and is decoupled from the drivetrain to reduce friction.

Hybrid Drive Operation
The electric propulsion motor alone powers the front wheels, as the gasoline engine (decoupled from the drive wheels) powers the electric-generator motor, which in turn provides power to the battery pack. This allows the gas engine-generator motor combo to supplement the battery by providing added electrical power to the propulsion motor or, alternatively, to charge the battery. In this type of operation, the system works as a "series hybrid." The electric propulsion motor offers crisp acceleration, and can reach maximum torque almost instantaneously, thanks to electrical power that can be supplied from both the gas engine-powered motor/generator and the battery.

Engine Drive Operation
When cruising at medium to high speeds, the high-efficiency Atkinson-cycle i-VTEC gasoline engine provides propulsion via a high capacity lock-up clutch, which connects the generator motor (always linked to the engine) and the electric drive motor, effectively sending motive power directly from the engine to the drive wheels. In this type mode, the system works as a "parallel hybrid" where both the gasoline engine and, when required – for instance upon quick acceleration – the electric propulsion motor, both provide power to the wheels. The i-MMD powertrain operates without the use of a conventional transmission.

2.0-liter Inline 4-cylinder Atkinson-Cycle Engine
The 2018 Accord Hybrid's third-generation i-MMD system utilizes a 2.0-liter DOHC i-VTEC 4-cylinder Atkinson-cycle engine that develops a peak 143 horsepower at 6200 rpm and 129 lb.-ft. of torque at 3500 rpm. Advances in engine control tuning together with other technologies combine to create excellent power characteristics, exceptional fuel efficiency and very low exhaust emissions. Key contributors to the improved thermal of efficient of the engine include improved exhaust gas recirculation and reductions in operating friction. This clean-running engine meets LEV3- AT-PZEV (SULEV30)/Interim Tier3 Bin30 emission standards, while contributing to the Accord Hybrid's total system output of 212 horsepower.

Since the gasoline engine can be decoupled from the rest of the hybrid powertrain, it only operates as needed. Depending on the state of battery charge and other parameters, the engine will automatically shut off during deceleration and when the vehicle is at a stop or operating under battery power. When needed, the gasoline engine restarts automatically, without action from the driver.

Engine Block, Crankshaft and Pistons
The engine has a displacement of 1,993cc. Cast-in iron cylinder liners provide long-lasting durability. Each journal on the forged-steel crankshaft is micro-polished to reduce internal friction. To improve smoothness throughout the rpm range and help lower noise levels, the Accord Hybrid is fitted with an internal balancer unit. Consisting of a pair of chain-driven counter-rotating shafts located in the oil pan, the balancing system helps quell the inherent second-order harmonic vibrations that are normally associated with inline 4-cylinder engines.

The 2.0-liter engine has cylinder bores offset by 6.0 mm from the crankshaft to help reduce piston-sliding friction. This gives the connecting rods a more favorable angle during each power stroke, which reduces side loading on the pistons and, in turn, improves efficiency. The lightweight pistons have a carefully optimized skirt design to minimize reciprocating weight, and reduced weight minimizes vibration and increases operating efficiency.

Cylinder Head and Valvetrain
The Accord Hybrid engine has a lightweight cylinder head that is made of pressure-cast aluminum alloy. A silent chain drives dual overhead cams and four valves per cylinder. The cam drive is maintenance free throughout the life of the engine.

To help boost fuel efficiency and power, the engine has a 34-degree included angle between the intake and exhaust valves. The narrow valve angle decreases the surface-to-volume ratio and helps create a flatter, more compact combustion chamber that reduces unburned hydrocarbon emissions. This combustion chamber shape and the precise control enables a high compression ratio of 13.5:1, yet the engine still operates on regular unleaded fuel.

VTEC Valve Control System
The Accord Hybrid's 2.0-liter DOHC 16-valve i-VTEC engine uses an advanced valve-control system to combine high power output with high fuel efficiency and low emissions. The system combines E-VTC (Electronic Variable Timing Control), which continuously adjusts the intake camshaft phase, with Variable Valve Timing and Lift Electronic Control (VTEC), which changes the lift profile, timing and duration of the intake valves' operation.

High-Efficiency Dual Bed Catalytic Converter
A key contributor to the Accord Hybrid's excellent emission performance is a single dual-bed catalytic converter. The converter mounts directly to the front of the cylinder head, close coupled for fast activation after the engine is started. It uses a thin-wall design that increases internal reaction area and improves efficiency. A high-efficiency exhaust system and the dual-bed, high-density catalytic converter help the Accord engine meet stringent LEV3- AT-PZEV(SULEV30)/Interim Tier3 Bin30 standards, which require reduced greenhouse gases compared to lower standards.

Heat Recovery Device
The heat recovery device contributes to the third-generation i-MMD's efficiency by helping to reduce power-robbing friction, particularly during cold-weather startup and initial operation, prior to engine warmup. Located downstream on the exhaust system, the heat recovery device uses hot exhaust gas to warm engine coolant quicker, especially during cold weather conditions. This brings the engine up to normal operating temperature quicker, reducing internal friction and allowing the i-MMD to operate in electric mode earlier. This helps improve fuel efficiency during cold weather operation.

Electric Motors
The 2018 Accord Hybrid uses two new-generation electric motors, a propulsion motor that drives the wheels and a generator motor that produces electricity, both of which have been upgraded from the previous generation i-MMD. The Honda-developed electric motors that are the first permanent magnet drive motors in the world to use magnets containing no heavy rare-earth metals. The propulsion motor is rated at 181 horsepower and 232 lb.-ft. of torque.

When in regenerative mode, the propulsion motor converts the kinetic energy of the decelerating vehicle into electrical energy to recharge the battery. Its operation is seamlessly coordinated with the Accord Hybrid's electric-servo braking system. (See the Chassis section for more information.) A separate generator motor is driven by the gasoline engine to generate electric energy to drive the propulsion motor when the vehicle is operating in Hybrid Drive Mode. This generator motor can also restart the gasoline engine when the vehicle is in idle-stop mode.

Intelligent Power Unit (IPU)
The Accord Hybrid's completely reworked intelligent Power unit (IPU) is now 32-percent more compact and has been repositioned under the rear seat base, instead of in the trunk, behind the rear seatback as in the previous generation Accord Hybrid. This repositioning means that the Accord Hybrid offers the same roomy trunk utility and 60/40 split-folding rear seatback versatility of the non-hybrid Accord models. The IPU packages a reconfigured Li-Ion battery pack that powers the Accord Hybrid's electric propulsion motor. Improved battery control systems and revised battery chemistry allow the new battery to operate over a broader state-of-charge range for improved efficiency.

The battery pack is recharged by the propulsion motor operating in regenerative braking mode, and by the generator motor, which is powered by the gasoline engine. Battery temperature is controlled by a fan system that pulls air from the interior of the vehicle via vents located beneath the rear seat bottom. The battery pack is covered by a special warranty that covers defects in material and workmanship for eight-years/100,000-miles or ten-year/150,000 miles depending on the state of purchase/registration.

Power Control Unit (PCU)
The Power Control Unit (PCU), which dictates the power management strategy of the two-motor hybrid system, including motor power and battery recharge, now includes the DC/DC converter and is mounted in the engine compartment.

Drive Force Transfer
Just like the previous model, the Accord Hybrid is not equipped with a conventional mechanical transmission. Instead, motive force transfer is accomplished through the interaction of the Accord Hybrid's gasoline engine and two electric motors. Coordinated by the IPU, this form of drive force transfer offers smooth and predictable acceleration matched with efficient low-rpm highway cruising when the gasoline engine is in operation. Gasoline engine shutdown is seamlessly integrated into the operation of the Accord Hybrid when appropriate.

The drive force transfer system operates without the need for a torque converter, mechanical pulley or belt. It instead uses two motors for driving and generating power. The system is optimally and rapidly able to control both engine and electric motor rotation in order to deliver higher fuel efficiency and quicker engine response in each driving mode.

When cruising at mid- or high-speeds in the high-efficiency range of the engine, a lock-up clutch is engaged, connecting the drive motor to the generator motor to transmit engine torque directly to the drive wheels as efficiently as possible. In EV Drive operation, when the battery-powered drive motor is used for either acceleration or regenerative braking, a clutch disengages the stopped gasoline engine from the drivetrain to eliminate efficiency loss from mechanical friction in the engine.

Improving efficiency and reducing weight and size, the drive force transfer system of the second-generation i-MMD integrates the torque limiter within the flywheel.

Deceleration Selector Paddles
In the Accord Hybrid, new steering wheel-mounted selector paddles allow the driver to select between four levels of regenerative braking performance. The right paddle adds regenerative braking (displayed visually on the instrument panel) and the left paddle reduces regenerative braking.

Common Features for All Engines

Drive-by-Wire™ Throttle System
The Accord's Drive-by-Wire™ throttle system replaces a conventional throttle cable with smart electronics that "connect" the accelerator pedal to a throttle valve inside the throttle body. The result is less under-hood clutter and lower weight, as well as quicker and more accurate throttle actuation. Moreover, a specially programmed "gain" rate between the throttle pedal and engine offers improved drivability and optimized engine response to suit specific driving conditions.

Honda's Drive-by-Wire™ throttle system evaluates the current driving conditions by monitoring throttle pedal position, throttle valve position, engine speed (rpm) and road speed. This information is used to define the throttle control sensitivity that gives the Accord's throttle pedal a predictable and responsive feel that meets driver expectations.

Close-Coupled Catalyst
All Accord engines have their exhaust manifold cast directly into the aluminum alloy cylinder head to reduce weight and complexity, and to position each primary catalytic converter as close as possible to the combustion chambers. A high-efficiency converter mounts directly to the exhaust port of the cylinder head for extremely rapid converter activation after engine startup.

Friction Reducing Technology
All the Accord's engines make use of friction-reducing technologies designed to improve engine efficiency. The outer skirts of lightweight aluminum pistons feature a low-friction coating applied in a unique pattern. The result is reduced overall friction as the pistons move within the cylinder bores. Plateau honing further lowers the friction level between the pistons and the cylinders by creating an ultra-smooth surface. Plateau honing is a 2-stage machining process that uses two grinding processes instead of the more conventional single honing process. This also enhances the long-term wear characteristics of the engine. Low viscosity oil (0W-20) also reduces friction. Other contributors to overall operating efficiency are a special 2-stage oil pump relief valve, low-friction oil seals, special low-drag piston ring design, low-friction cam chain and a lightweight crankshaft.

Emissions Certifications

Accord 1.5-liter turbo: LEV3-ULEV50; LEV3-SULEV30
Accord 2.0-liter turbo: LEV3-ULEV50; LEV3-SULEV30
Accord Hybrid: LEV3-SULEV30

All three Accord engines are engineered for low emissions, and are certified to their respective level of emissions performance for 120,000 miles.

100,000+/- Mile Tune-up Intervals
The Accord's three available powerplants require no scheduled maintenance for 100,000+/- miles or more, other than periodic inspections and normal fluid and filter replacements. The first tune-up includes water pump inspection, valve adjustment, and the installation of new spark plugs.

Maintenance Minder™ System
To eliminate unnecessary service stops while ensuring that the vehicle is properly maintained, the Accord has a Maintenance Minder™ system that continually monitors the vehicle's operating condition. When maintenance is required, the driver is alerted via a message on the Driver Information Interface (DII).

The Maintenance Minder™ system monitors operating conditions such as oil and coolant temperature along with engine speed to determine the proper service intervals. Depending on operating conditions, oil change intervals can be extended to a maximum of 10,000 miles, potentially sparing the owner considerable expense and inconvenience over the life of the vehicle. The owner-resettable system monitors all normal service parts and systems, including engine oil and filter, tire rotation, air-cleaner, transmission fluid, spark plugs, engine coolant, brake pads and more. To reduce the potential for driver distraction, maintenance alerts are presented only when the ignition is first turned on, not while driving.

Powertrain Feature Comparisons

Feature	2017 Accord 2.4	2018 Accord 1.5L Turbo
Engine Type	In-Line 4-Cylinder	Turbocharged In-Line 4-Cylinder
Displacement (cc)	2356	1498
Horsepower @ rpm (SAE net)	185 @ 6400	192 @ 5500
Torque (lb.-ft. @ rpm SAE net)	181 @ 3900	192 @ 1600-5000
Bore and Stroke (mm)	87 x 99.1	73 x 89.5
Compression Ratio	11.1:1	10.3:1
Direct Ignition	•	•
Valvetrain	16-Valve DOHC i-VTEC®	16-Valve DOHC VTEC
Fuel Delivery	Direct	Direct
Drive-by-Wire™ Throttle System	•	•
Transmission	6-Speed Manual, CVT	6-Speed Manual, CVT
Front-Wheel Drive	•	•

Feature	2017 Accord V6	2018 Accord 2.0 Turbo
Engine Type	V6	Turbocharged In-Line 4-Cylinder
Displacement (cc)	3471	1996
Horsepower @ rpm (SAE net)	278 @ 6200	252 @ 6500
Torque (lb.-ft. @ rpm SAE net)	252 @ 4900	273 @ 1600-4000
Bore and Stroke (mm)	89 x 93	86 x 85.9
Compression Ratio	10.5:1	9.8:1
Direct Ignition	•	•
Valvetrain	24-Valve SOHC i-VTEC®	16-Valve DOHC VTEC
Fuel Delivery	Multi-Point	Direct
Drive-by-Wire™ Throttle System	•	•
Transmission	6-Speed Automatic	6-Speed Manual, 10-Speed Automatic
Front-Wheel Drive	•	•

Feature	2017 Accord Hybrid	2018 Accord Hybrid
Engine Type	In-Line 4-Cylinder	In-Line 4-Cylinder
Displacement (cc)	1993	1993
Horsepower @ rpm (SAE net)	143 @ 6200	143 @ 6200
Torque (lb.-ft. @ rpm SAE net)	129 @ 4000	129 @ 3500
Bore and Stroke (mm)	81 x 96.7	81 x 96.7
Compression Ratio	13.0:1	13.5:1
Direct Ignition	•	•
Valvetrain	16-Valve DOHC i-VTEC®, Atkinson Cycle	16-Valve DOHC i-VTEC®, Atkinson Cycle
Fuel Delivery	Multi-Point	Multi-Point
Hybrid Electric Drive Motor	AC Synchronous Permanent-Magnet	AC Synchronous Permanent-Magnet
Horsepower @ rpm (SAE net)	181 @ 5,000-6,000	181 @ 5,000-6,000
Torque @ rpm (SAE net)	232 lb.-ft. @ 0-2,000	232 lb.-ft. @ 0-2,000
Total System Horsepower @ rpm	212 @ 6,200	212 @ 6200
Hybrid Battery	Lithium-Ion	Lithium-Ion
Drive-by-Wire™ Throttle System	•	•
Transmission	None (uses Drive Force Transfer System)	None (uses Drive Force Transfer System)
Front-Wheel Drive	•	•

Accord Powertrain Specifications

Feature	2018 Accord 1.5L Turbo	2018 Accord 2.0L Turbo	2018 Accord Hybrid
Engine Type	Turbocharged In-Line 4-Cylinder	Turbocharged In-Line 4-Cylinder	In-Line 4-Cylinder
Displacement (cc)	1498	1996	1993
Horsepower @ rpm (SAE net)	192 @ 5500	252 @ 6500	143 @ 6200
Torque (lb.-ft. @ rpm SAE net)	192 @ 1600-5000	273 @ 1500-4000	129 @ 3500
Bore and Stroke (mm)	73 x 89.5	86 x 85.9	81 x 96.7
Compression Ratio	10.3:1	9.8:1	13.5:1
Maximum Boost (psi)	20.2	20.8	NA
Fuel Injection	Direct	Direct	Multi-Point
Valvetrain	16-Valve DOHC w/dual VTC and VTEC	16-Valve DOHC w/dual VTC and VTEC	16-Valve DOHC i-VTEC w/intake VTC
Drive-by-Wire™ Throttle System	•	•	•
Low-Inertia MONO Turbocharger	•	•	—
Hybrid Electric Drive Motor	—	—	AC Synchronous Permanent-Magnet
Horsepower @ rpm	—	—	181@5,000
Torque @ rpm	—	—	232 lb.-ft.@0-2,000
Total System Horsepower @ rpm	—	—	212 @ 6200
Hybrid Battery	—	—	Lithium-Ion
100K +/- Miles No Scheduled Tune-Ups	•	•	•

Accord Turbo Transmissions

Feature	LX	EX	EX-L	EX-L Navi	Touring	Sport 1.5	Sport 2.0
6-Speed Manual						•	•
Gear Ratios: 1st: 3.643 2nd: 2.080, 3rd: 1.361, 4th: 1.024, 5th: 0.830, 6th: 0.686, Reverse: 3.673, Final Drive:4.105 (1.5 Liter) 1st: 3.625, 2nd: 2.115, 3rd: 1.529, 4th: 1.125, 5th: 0.848, 6th: 0.686, Reverse: 3.758, Final Drive: 3.842 (2.0 Liter)
Continuously Variable Transmission (CVT) (1.5 Liter)	•	•	•	•	•	•
Gear Ratios: Forward: 2.645～0.405, Reverse: 1.859～1.265, Final Drive: 3.238
10-Speed Automatic Transmission with Shift-By-Wire (SBW) and paddle shifters (2.0 Liter)				•	•		•
Gear Ratios: 1st: 5.340, 2nd: 3.329, 3rd: 2.224, 4th: 1.625, 5th: 1.327, 6th: 1.018, 7th: 0.796, 8th: 0.665, 9th: 0.591, 10th: 0.527, Reverse: 4.045, Final Drive: 3.550

Fuel Economy and Emissions Ratings

Ratings	2018 Accord 1.5 Turbo with 6MT	2018 Accord 1.5 Turbo with CVT	2018 Accord 2.0 Turbo with 6MT	2018 Accord 2.0 Turbo with 10AT	2018 Accord Hybrid
EPA Fuel Economy Ratings¹ (city / highway/ combined)	26/35/30 (Sport)	30/38/33 (LX, EX, EX-L) 29/35/31 (Sport, Touring)	City/Hwy Targets Only 22/32 (Sport)	City/Hwy Targets Only 23/34 (EX-L) 22/32 (Spt., Trg.)	TBA
Recommen-ded fuel	Regular unleaded 87 octane	Regular unleaded 87 octane	Regular unleaded 87 octane	Regular unleaded 87 octane	Regular unleaded 87 octane
CARB emissions rating	LEV3-ULEV50; LEV3-SULEV30	LEV3-SULEV30	LEV3-SULEV30	LEV3-SULEV30	LEV3-SULEV30