C5 vacuum problem - no vac to interior
Thread Starter
Racer
Joined: Oct 2001
Posts: 304
Likes: 0
From: sometown new york
C5 vacuum problem - no vac to interior
A vacuum schematic, a vacuum schematic, my kingdom for a C5 vacuum schematic!
I still can't find where I'm loosing vacuum to the interior. The vent selector switch is not working. All other vacuum appears to be working. Brakes are good and the motor is fine. There is no vacuum feeding the vacuum check valve under the battery. Because GM hid the vacuum line in the wiring harness, I can't trace it visually. I've tried smoke and still can't find the problem. :mad
I still can't find where I'm loosing vacuum to the interior. The vent selector switch is not working. All other vacuum appears to be working. Brakes are good and the motor is fine. There is no vacuum feeding the vacuum check valve under the battery. Because GM hid the vacuum line in the wiring harness, I can't trace it visually. I've tried smoke and still can't find the problem. :mad
Pro
Joined: Mar 2001
Posts: 512
Likes: 19
From: Greensboro NC
Re: C5 vacuum problem - no vac to interior (connellyh)
You more than likely have a battery that's leaking acid onto the vaccum line under the battery. Remove the passenger inner wheel well and look for battery acid. If you find battery acid, neutralize it and clean it up very well. Then repair/replace the vaccum line that goes to the back of the intake manifold and you should be set.
Frank
Frank
Thread Starter
Racer
Joined: Oct 2001
Posts: 304
Likes: 0
From: sometown new york
Re: C5 vacuum problem - no vac to interior (QwikSilvr)
I had that problem a few months ago. I thoroughly cleaned up and I replaced the check valve and the hard lines up to the wiring harness. The new battery is not leaking. Just to make sure, I pulled the battery, inspected the lines and tested the check valve. Everything is fine. The problem is upstream of the point where the vacuum check valve feed line exits the wiring harness.
