S2 - Check For RPM Drop

- Key "OFF".

- Connect engine tachometer.

- Start engine.

- Disconnect Idle Air Control (IAC) solenoid.

- Does rpm drop or engine stall?

Yes -- Reconnect IAC solenoid.

Vehicle equipped with Manifold Absolute Pressure (MAP) sensor go to S3. S3 - Power to MAP/BARO Sensor Test

Vehicle equipped with Mass Air Flow (MAF) sensor go to S8. S8 - Check EGR Vacuum

No -- Go to pinpoint test step KE4.