HVAC Help!!
Thread Starter
Instructor
Joined: Jun 2011
Posts: 158
Likes: 0
From: Atlanta GA
HVAC Help!!
I recently repaired 2 broken vacuum lines under the battery tray where acid had eaten through them. I now have good vacuum everywhere and the check valve is also functioning correctly. The only codes i have ever experienced are lean codes. Moral of the story my AC still blows through all the vents no matter what setting it is on and this atlanta heat is literally killing me. I have had the car for over a year and this has always been an issue. Any comments as to a potential fix would be appreciated! Thanks
Instructor
Joined: Jul 2011
Posts: 110
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From: Atlanta GA
Thread Starter
Instructor
Joined: Jun 2011
Posts: 158
Likes: 0
From: Atlanta GA
I don't have a vacuum gauge but it was very strong and consistent right before the check valve. The hose I replaceed the broken pieces with was a few inches longer as well because I had trouble routing it the same way through the tight spaces.
Tech Contributor
Joined: Jan 2007
Posts: 19,465
Likes: 1,167
From: Dyer, IN
Not trying to give you a hard time, but if you don't know exactly how much vacuum you are pulling, then you don't know if it's good or not. Bottom line, buy a gauge....very inexpensive at any auto parts store. If you did not measure the vacuum to the distribution manifold inside the car, you have not covered all the bases. For a stock cam, expect to see 20-23 inches of Hg.
Melting Slicks
Joined: Jul 2006
Posts: 2,332
Likes: 31
From: Silver Spring MD
Mine had both supply and the line into the firewall acidified
I had to replace parts of the supply line coming from the manifold and in the middle of the trunk cable coming across the engine as well as the line which terminates inside the car and goes to the purple connector which goes on the vacuum switch located on the passanger side under the dash.
My vacuum check valve located inside the rear of the right front fender was also bad. It is like $7 at the dealer and about $4.75 at Advance Auto.
Check at the purple ended hard line under the dash. If no vacuum there none of the actuators will operate and the air will come out of all the outlets at the same time.
PS: I have gone through 3 vacuum check valves. Don't know why but one of the ports breaks off. To get to it just remove a couple of sheet metal screws at the rear of the front wheelwell and pry gently the composite fender away enough to get your hand inside. Helps if you raise the right front side of the car. I used Rhino ramps on the front wheels to do this.
My vacuum check valve located inside the rear of the right front fender was also bad. It is like $7 at the dealer and about $4.75 at Advance Auto.
Check at the purple ended hard line under the dash. If no vacuum there none of the actuators will operate and the air will come out of all the outlets at the same time.
PS: I have gone through 3 vacuum check valves. Don't know why but one of the ports breaks off. To get to it just remove a couple of sheet metal screws at the rear of the front wheelwell and pry gently the composite fender away enough to get your hand inside. Helps if you raise the right front side of the car. I used Rhino ramps on the front wheels to do this.
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Thread Starter
Instructor
Joined: Jun 2011
Posts: 158
Likes: 0
From: Atlanta GA
Thanks big hank! I just picked up a vacuum gauge and need to dig a little deeper as both of you have suggested. Ill keep you informed hopefully ice cold fast blowing air is in my near future.
Thread Starter
Instructor
Joined: Jun 2011
Posts: 158
Likes: 0
From: Atlanta GA
I tested for vacuum at the block inside the car and had none. So I spliced into the harness coming through the firewall and battery acid went everywhere. I pulled the vacuum line out and it looked like swiss cheese for about 4 inches. I relplaced the line and finally my AC blows out the correct vents and works on all modes. Thank you everyone for your help and for starting these incredible threads!!