For 1990-2009 cars only
- Operate the engine until it reaches normal operating temperature.
- Disconnect the engine vacuum harness from the vacuum pump inlet pipe.
- Connect the J 23951 Manometer (or any standard vacuum gage) to the vacuum pump inlet pipe.
- Operate the engine at an idle for 30 seconds. If the engine operates for longer than 30 seconds, or if the engine does not operate at an idle, vent the manometer and repeat this step.
- While operating the engine, observe the manometer reading. Refer to Engine Mechanical Specifications.
- If the vacuum pump fails to meet the minimum specifications, replace the vacuum pump and retest.
