Bonneville V6-231 3.8L VIN 3 SFI (1988)
Idle Speed: Adjustments
Minimum Air Rate - Fuel Injection Only
Throttle Position Sensor and IAC Specifications
Idle speed is speed is controlled by the ECM through the Idle Speed Control motor and is not adjustable. The minimum air rate is adjustable as follows.
1.
Ground diagnostic terminal, turn ignition on, but do not start engine.
2.
Wait 45 seconds for IAC to fully seat, then with ignition still on disconnect IAC connector.
3.
Disconnect the distributor set timing connector.
4.
Start engine and allow engine to go into "Closed Loop".
5.
Remove ground from diagnostic terminal.
6.
Adjust idle speed to specifications using throttle stop screw.
7.
Turn ignition off and reconnect IAC connector.
8.
Adjust TPS voltage if necessary:
With ignition "ON" use a scan tool or 3 jumper wires to adjust TPS sensor to correct voltage specification.
Tighten screws, then recheck reading to insure adjustment has not changed.
9.
Start engine and check for proper idle operation.
