Purge Port Vacuum
This check is to be performed with the engine coolant temperature at 176 - 205°F (80 - 95°C).
Purge Control Vacuum Inspection:
1. Disconnect the vacuum hose from the Throttle Body purge hose fitting and connect a hand vacuum pump to the fitting.
Purge Port Vacuum Curve:
2. Start the engine and check to see that, after increasing the engine speed, vacuum rises in proportion with RPM.
NOTE: If the vacuum does not respond as specified in the test, it is probable that the throttle body requires cleaning.