Operation CHARM: Car repair manuals for everyone.

Deceleration Mode

THIS IS AN OPEN LOOP MODE.

During deceleration the the Powertrain Control Module (PCM) receives inputs from:

- Air Conditioning Control Position

- Battery voltage

- Camshaft position (CMP) sensor

- Engine coolant temperature (ECT) sensor

- Manifold Absolute Pressure (MAP) sensor

- Intake air temperature (IAT) sensor

- Crankshaft position (CKP) sensor

- Throttle Position Sensor (TPS)

Based On These Inputs The PCM Will:
- Adjust engine idle speed through the IAC motor.

- Adjust ignition timing.

- Operate A/C Compressor Clutch relay (if selected).

- Ignore oxygen sensor input. The PCM will enter fuel cut-off strategy (under hard deceleration).

- Determine proper injector pulse width and continue injection (under normal deceleration).