GM Lumina/Silhouette/Transport APVs 1990-1999 Repair Guide

Evaporative Canister


To limit gasoline vapor discharge into the air when the vehicle is not operating. This system transfers fuel vapors from the fuel tank to a charcoal canister storage device. This canister absorbs fuel vapors and stores them until they can be burned in the engine. When the engine is running, the fuel vapor is purged from the carbon element by intake air flow and consumed in the normal combustion process. The EVAP purge solenoid valve allows manifold vacuum to purge the canister.

Poor idle, stalling and poor driveability can be caused by:

Hoses split, cracked and/or not connected properly
Damaged canister
Malfunctioning purge solenoid


Inspect the canister for cracks or damage and for fuel leaks. If either condition is found it will be necessary to replace the canister. Also check the condition of the hoses. If necessary, replace them. Be sure to use hoses marked EVAP.

See Figure 1

Click image to see an enlarged view

Fig. Fig. 1: View of the EVAP canister mounted in the engine compartment