Diagnostic Aids
WARNING: This page is about a different car, the 2003 Pontiac Aztek and 2003 Buick Rendezvous. However, it is still accessible from the selected car via links, so may be relevant.
- Operate vehicle under condition of customer's concern. Under high temperature conditions fuel vapors may increase to a point of EVAP canister vapor saturation. Fuel vapors would then be released into atmosphere. Once engine is running and EVAP purge is enabled, all fuel vapor release would be eliminated.
- Test for fuel leaking in fuel tank, rear tank if equipped, and fuel feed and return pipes.
- Test for fuel vapor leaks in fuel tank, fill limiter vent valve and rollover valves, fuel fill pipe, hose and fuel fill cap, fuel sender housing and seal, Fuel Tank Pressure (FTP) sensor seal and EVAP vapor pipe.
- Movement of EVAP pipes or fuel pipes may help find an intermittent condition.