Diagnostic Trouble Code (DTC) Information

Diagnostic trouble code (DTC) information ECM-420D

Condition




When the control module activates evaporative emission system (EVAP) control, the idle air trim or short-term fuel trim will change. The diagnostic trouble code (DTC) is stored if the engine control module (ECM) does not detect any change in the idle air trim or in the long term fuel trim when evaporative emission (EVAP) control is active. The engine control module (ECM) interprets this as a damaged evaporative emission (EVAP) system.

Substitute value
None.

Possible source
- Blocked hose between the EVAP canister and the EVAP canister purge valve
- Blocked hose between the evaporative emission system (EVAP) valve and the intake manifold
- Damaged evaporative emission system (EVAP) valve.

Fault symptom[s]
- Malfunction indicator lamp (MIL) lit.