Evaporative Emissions System: Testing and Inspection

Purge Port Vacuum Inspection

Purge Control System:

1. Run engine at idle until warm [80-95°C (176-203°F)].
2. Disconnect the vacuum hose (red stripe) from the throttle body purge nipple and connect a vacuum gauge to the nipple.
3. START the engine and raise the engine speed to 2,500-3,000 rpm over a period of approximately 30 seconds while observing the vacuum gauge. Vacuum should remain constant regardless of engine speed.

Purge Port Vacuum Test:

NOTE: No vacuum at this nipple could indicate that the nipple is clogged. Clean nipple and retest vacuum.