Evaporative Emissions System: Testing and Inspection

FUNCTIONAL TEST OF THE VAPOR CANISTER

TEST DESCRIPTION:

1. Install a short piece of hose on the lower tube of the purge valve, and attempt to blow air through the hose. Little or no air should pass into the canister. A small amount of air will pass into the canister if the canister has a constant purge hole.

2. Using a hand held vacuum pump, apply 15" Hg (51 kPa) of vacuum to the control valve tube (upper tube). The diaphragm should hold vacuum for at least 20 seconds. If it does not hold vacuum, the diaphragm is bad and the canister must be replaced.