Dieseling, Run-On. Chevrolet Express (CNG) 2001

For 1990-2009 cars only

Makes 🢒 Chevrolet 🢒 2001 🢒 Express (CNG) 🢒 Engine 🢒 Engine Controls - 5.0L and 5.7L 🢒 Dieseling, Run-On

Checks

Action

DEFINITION: The engine continues to run when the ignition is turned OFF, but usually runs very roughly.

Preliminary Checks

Refer to Important Preliminary Checks in Symptoms - Engine Controls .

Fuel System Checks

•	Test for proper EVAP Purge system operation.

•	Test the fuel injectors for leakage.

•	Inspect for correct throttle blade adjustment, if applicable.

•	Perform the fuel system diagnostic procedure. Refer to Fuel System Diagnosis .

Additional Checks

If the engine continues to run smoothly when the ignition is turned OFF inspect for the following:

•	Proper ignition switch adjustment

•	A short to voltage in the control modules (Alternative Fuel ECM, gasoline VCM / PCM or ECM) ignition feed circuit.