Deceleration Fuel Cut-Off

WARNING: This page is about a different variant/trim than selected.

When the driver releases the accelerator pedal, air flow into the engine is reduced. The ECM monitors the corresponding changes in the throttle position, MAP, and MAF. The ECM shuts OFF fuel completely if the deceleration is very rapid, or for long periods, such as closed-throttle coast-down. The fuel shuts OFF in order to prevent damage to the catalytic converter and saves fuel by not running the engine. This mode is activated quickly and for a longer duration in the eAssist hybrid vehicle.

While in deceleration fuel cut-off mode, the torque converter stays locked allowing the drive motor to be coupled to the wheels (through engine and trans) to recharge the hybrid batteries via regenerative braking. The drive motor can also quickly react to help smooth driveline disturbances (downshifts), or provide assist for a smooth take off when the accelerator is depressed. If the vehicle is brought to a complete stop the drive motor spins the engine bringing it to a smooth stop and is properly positioned for a smooth restart.