Power Booster Check Valve Test

WARNING: This page is about a different car, the 2005 Jeep Liberty. However, it is still accessible from the selected car via links, so may be relevant.

Disconnect vacuum hose from check valve.
Remove check valve and valve seal from booster.
Use a hand operated vacuum pump for test.
Apply 15-20 inches vacuum at large end of check valve. See Figure.
Vacuum should hold steady. If gauge on pump indicates vacuum loss, check valve is faulty and should be replaced.

Fig 1: Typical - Vacuum Check Valve And Seal

Courtesy of DAIMLERCHRYSLER CORP.

1 - BOOSTER CHECK VALVE

2 - APPLY TEST VACUUM HERE

3 - VALVE SEAL