2002 s10 ZR2 Vent Problem

[boneil]

I have found someone within this forum who had the same issue I am having but I'm still search for my solution. My problem is my air/heat system is stuck on "vent". I have replaced the dash controls with speed, temp, and mode. My situation gets better because after I replaced the dash controls(one piece), my air system worked fine for a few days, then went back to "vent" only. I have pulled the dash apart and checked the vacuum lines behind the glovebox, next to the gas pedel, and checked under the hood for any loose/disconnected lines. I'm getting about 80% "vent" and 20% on "other" modes. This leads me to believe its a leak in a vacuum line... but where?

I have had no luck figuring out what is causing the system not to switch to anything other then vent. I dont put anything on the dash, so nothing has spilled/dropped down the vents to block them open. And this problem just occured out of the blue. My truck only has 44k miles on it and this is a problem that should not be happening this soon in my trucks life. I will be using this weekend to disassemble my truck again, insearch of the problem and hopefully a solution. I dont want to keep replacing parts for the fun of it at 100$/part. If anyone has had this problem or knows how to fix it, please let me know.

Thanks in advance, Bryan

[BlazerLT]

Check the vacuum hoses in the engine bay.

[boneil]

I have looked throughout the engine bay and every hose seems to be attached and inorder. I'm going to rip apart the dash again and check the vacuum lines that run all over. This is getting real annoying that I can't find this leak/block or whatever it may be.

Any clues to what I might not have checked under the dash would be of some help. I've check behind the glove box, behind the controls, and next to the pedels under the column, and all seems to be connected and working.

Thanks Again For the Advice, Bryan

[Jerry80871852]

Originally Posted by boneil

I have looked throughout the engine bay and every hose seems to be attached and inorder. I'm going to rip apart the dash again and check the vacuum lines that run all over. This is getting real annoying that I can't find this leak/block or whatever it may be.

Any clues to what I might not have checked under the dash would be of some help. I've check behind the glove box, behind the controls, and next to the pedels under the column, and all seems to be connected and working.

Thanks Again For the Advice, Bryan

A long time ago I had such a problem similar to that on a 1970 Duster, had to replace the switch that controls the vents, it had gone out and would not let the vacuum thru to open the vent.

Wish I still had that 340, it would run a hole in the wind. But evertime I would go some where the cops would stop me.

Seems that with the front end lower, the back end raised up, very wide tires on the back, with headers and no mufflers, and extremely strange idle becasue of the wild cam, they though I was a hot rodder and would not leave me alone.

[boneil]

I have already replaced the controls for the vent, they were part of the control unit that I bought/installed. The weather is finally getting decent so I'm going to try and dig around some more.

Any new clues would be appreciated.

- bryan

[Jerry80871852]

Originally Posted by boneil

I have already replaced the controls for the vent, they were part of the control unit that I bought/installed. The weather is finally getting decent so I'm going to try and dig around some more.

Any new clues would be appreciated.

- bryan

I had a 85 Chevy pickup that I put a long block in.

I had not hooked up a vacuum line to the engine in the right place, it took me about a month of switching the vacuum lines around before the vent doors would open and close properly.

Another though, do not some vacuum lines have a small valve in them to keep the vacuum from going backwards that can stick and not allow vacuum pressure to go thru? Do not know if yours would or not.

Just trying to throw ideas out.

[boneil]

Where to begin?
To start, I would like to say that sites like this one are very helpful for people who have to fix their "new" cars/trucks on their own. I figured I would come back to actually explain how I fixed this problem, so that one day this might actually help some other unfortunant soul who has a Chevy.
After a month of double & triple checking every hose, and connection under the dash and around the engine, it all comes down to a falty replacement part from the DEALER.
You have to love the fact that my original vent mode control went bad at only 44,000 miles. Then, after say 3 days, my Chevy luck gets even better when the replacement part goes bad too. After a few days of dealing with the DEALER parts service guys, I get a new replacement part for my previous replacement part.
So finally, after a few weeks of having my dash ripped apart, I finally have a vehical that can blow air out of the defroster, vents and floor. AMAZING!

Thank God I have a 1992 Wrangler (with 222,200 miles) that I could drive to get to work everyday while my 2002 S-10(with 44,000) miles was sitting in my drive way.

Good luck to all who are searching for answers to why everything is breaking.

- Bryan

[brightdim03]

had that prob, "internal falure" dealership replaced mode actuator, also have your coolant sys looked at for oil seepage thats another thing that went on, they had to clean EVERYTHING and rplace half my heating/AC parts. the leak came from the transfer case vacumn switch

[chevy02]

We had this recurring problem starting at 30,000. The dealer replace the air controller twice and on the third time they replaced all the vacuum lines in addition to the air controller. And the 4th time they replaced both again and supposeable did something else which of course they didn't tell us and so far we've had about 20000 miles without a hiss or air controller failure (something was leaking into the vacuum lines and corroding the seal on the controller). Thankfully the first 2 times it went was under warranty and the dealer continued fixing it for free after the warranty because it wasn't fixed correctly when it was under warranty.