Power Booster Vacuum Test
WARNING: This page is about a different car, the 2005 Jeep Grand Cherokee. However, it is still accessible from the selected car via links, so may be relevant.
- Connect vacuum gauge (6) to booster check valve (4) with short length of hose (3) and T-fitting (2).
- Start and run engine at curb idle speed for one minute.
- Observe the vacuum supply. If vacuum supply is not adequate, repair vacuum supply.
- Clamp (1) hose (7) shut between intake vacuum source (5) and check valve (4).
- Stop engine and observe vacuum gauge (6).
- If vacuum drops more than one inch HG (33 millibars) within 15 seconds, booster diaphragm or check valve is faulty.