Operation CHARM: Car repair manuals for everyone.
Manuals through 2025 now available!

Our trusted friends have launched a new website named LEMON, which has newer manuals. It also contains all the CHARM manuals.

LEMON is the spiritual successor to CHARM, I recommend you try it!

Link: lemon-manuals.la or lemon-manuals.org.ua

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Deceleration

PCM MONITORS:

- Engine Temperature (ECT Sensor)
- Manifold Vacuum (MAP Sensor)
- Throttle Position (TPS)
- Exhaust Gas Oxygen Content (HO2S)
- A/C Switch Status
- Battery Voltage
- Camshaft and Crankshaft Position (CMP and CKP Sensors)

UNDER NORMAL DECELERATION, PCM:

Continues normal (reduced) injection.

De-energizes EGR system, by grounding Electronic EGR Transducer (EET) solenoid.

UNDER HARD DECELERATION, (CLOSED THROTTLE AND ABRUPT INCREASE IN MANIFOLD VACUUM) THE PCM:

Ignores oxygen sensor input, and initiates fuel cut-off strategy, firing injector only once per engine revolution.

Disables EGR system, by grounding EGR solenoid.

Disables EVAP purge system, by grounding EVAP solenoid.