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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Wide Open Throttle Mode

This is an open loop mode.

The throttle position sensor notifies the PCM of a wide open throttle condition.

When the PCM senses a wide-open-throttle condition through the Throttle Position Sensor (TPS) it deenergizes the A/C compressor clutch relay.
- Once a wide open throttle condition is sensed the PCM de-energizes the A/C compressor clutch relay for 15 seconds.

The PCM does not monitor the heated oxygen sensor inputs during wide-open-throttle operation except for downstream heated oxygen sensor and both shorted diagnostics.
- The PCM adjusts injector pulse width to supply a predetermined amount of additional fuel.

During wide-open- throttle operation, the following inputs are received by the PCM:
- Intake air temperature
- Engine coolant temperature
- Engine speed
- Knock sensor
- Manifold absolute pressure
- Throttle position