Operation CHARM: Car repair manuals for everyone.

Evaporative Emissions System: Testing and Inspection

^ Poor idle, stalling and poor driveability can be caused by the following:
- Inoperative purge solenoid valve.
- Damaged canister.
- Hoses split, cracked and, or not connected to the proper tubes.
^ Evidence of fuel loss or fuel vapor odor can be caused by:
- Liquid fuel leaking from fuel lines.
- Cracked or damaged canister.
- Inoperative canister control valve.
- Vacuum hoses that are:
- Disconnected.
- Mis-routed-routed.
- Kinked.
- Deteriorated or damaged vapor hoses. If the solenoid valve is open, or is not receiving power, the canister can purge to the intake manifold at the incorrect time. This can allow extra fuel during warm-up, which can cause rough or unstable idle.