DeVille V8-4.9L VIN B (1995)
Throttle Position Sensor: Adjustments
Throttle Position (TP) Sensor Learn Procedure
A TP SENSOR LEARN routine has been implemented in the PCM software to allow the PCM to correct or offset the closed throttle signal value of the
TP sensor. If an improper TP sensor offset is maintained by the PCM, a high idle at closed throttle or stall condition may occur. Performing the TP
SENSOR LEARN procedure lets the PCM learn the correct TP sensor offset.
An IDLE LEARN routine has been implemented in the PCM software to allow for a loss of air flow through the throttle body during closed throttle
operation. This reduction in air flow can be caused by deposit buildup on the throttle valve.
The IDLE LEARN routine of the PCM calculates a throttle angle correction or offset that is used during closed throttle idle control. If an improper
throttle angle offset is maintained by the PCM, a high idle at closed throttle or stall condition may occur. Performing the IDLE LEARN procedure lets
the PCM learn the correct throttle angle offset.
The TP Sensor/Idle Learn procedure should be performed when:
^
The TP sensor is replaced.
^
The throttle body is replaced.
^
The PCM is replaced.
^
The battery is disconnected or replaced.
^
PCM Code P052 was set.
^
The ISC Actuator has been adjusted.
^
TP sensor adjustment procedure has been performed.
^
The minimum idle speed adjustment procedure has been performed.
To perform TP Sensor/Idle Learn:
1. Outside air temperature is 10°C (50°F) or greater.
2. Start engine and allow to idle for 13 minutes.
3. At end of 13 minutes, enter diagnostics (engine still running).
4. Turn ignition "OFF."
5. Wait a minimum of 20 seconds.
6. Turn ignition to "ON" (engine not running).
7. Enter diagnostics.
8. Turn ignition "OFF."
9. Wait a minimum of 20 seconds.
10. Turn ignition to "ON" (engine not running).
11. Enter diagnostics.
12. Turn ignition "OFF."
13. Wait a minimum of 20 seconds.
14. Start engine.
15. Apply brakes and place transaxle in "DRIVE" range.
16. Turn the Climate Control Panel (CCP) to "OFF" and allow engine to idle for at least 1 minute.
17. Turn the CCP to "AUTO," verify that A/C compressor engagement occurs. Allow engine to idle for at least 1 minute.
18. Place transaxle in "PARK" range and turn ignition to "OFF."
^
Make sure nothing is touching or obstructing the accelerator or brake pedals during the TP Sensor/Idle Learn procedure because this will
prevent the PCM from performing the learn routine.
^
Because of the engine load differences with the A/C "ON" versus "OFF," TP Sensor/Idle Learn must be allowed during both conditions.
