Questions and Answers

Chevy Monte Carlo A/C Problem Q. Hi, I have a 1996 Chevy Monte Carlo 3.1 liter engine. The car has 91,000 miles on it. I have been frustrated all summer long over a problem with the a/c. For whatever reason the air will not blow out through the A/C vents. It will only blow out through the defroster vents and at floor level.

This is the case whether I'm using the heater or the A/C. I have been told this is caused by a lack of vacuum.I have spent a lot of time searching for any unhooked vacuum lines and as of yet have found none. I am not a mechanic by any means,but at this point I'm inclined to think it is something other than an unhooked vacuum line.

I guess I should mention that I did do some work under the hood last winter, prior to using the A/C. The alternator, battery, spark plugs, spark plug wires and air filter all were changed. I thought maybe I accidentally unhooked something while doing these repairs, but as I previously stated I haven't found anything unhooked.I didn't have these problems when I used the A/C last year.

Any advice you can give me would be greatly appreciated.

Thanks,
Sam

A. Well, there is a main vacuum line under the hood that feeds the HVAC system. It's hooked to the intake manifold either near the throttle body or at the rear of intake plenum. It runs into a wire harness bundle & will look like a wire to you, just a little bigger in diameter. It is possibly broken or melted somewhere. Sometimes near the battery there is a gray line that falls apart due to battery acid.