I just bought a 1997 Monte Carlo LS with 35,000 miles. On a recent trip from Atlanta, GA to Louisville, KY I found that the dash vents stop blowing when I acclerate and then start again when I let off the gas. Has anyone heard of or had this problem?

Drew
1997 Monte Carlo

 

Does it do this only on hard acceleration or at all levels? My Monte shuts off the a/c compressor when I get on it @ WOT, like it disengages the compressor clutch to give it more power.

Other than that you may have a vac leak somewhere.

The vent system uses vac to open close vent doors.

 

most of the time there is a solinoid in there that is gettin a wrong sgnal for that and they dont shut the vents all the way or they open them at the wrong time LOL

But this actually sounds mor eto me that you have a vac. leak in the system or a hose that is cracked and not holding the right amout of Vac. presure so when you get in to it it uses the extr vacum for advance in the motor etc.... so it takes it away from the vac valve witch inturn opens the door to allow flow to stop

In a nut shell get under your dash and see where the vac,lines run and make sure they are good
also check the hoses under the hood for the same thing.
then find the fulty valve and replace if needed.
Good luck
If you start the car and get under the dash if there is a leak you should hear it it if it is sucking enough air threw it.

 

Thanks guys,

I haven't had a chance to get back to the site recently due to a move, thanks for your input. As it turns out a part of the vacuum line is broken and the check valve needs to be replaced. It will be nice to get this fixed ASAP due to the heat!

 

Cool, glad you found the problem!!!...

Moving is always fun............ Not....

 

I'm not sure about GM's but on my other car, 96 taurus, the pcm is supposed to turn off the AC during hard accelerations. I think at 3k is shuts it down. It kind of makes sense to do that since if you need to gun it, then why do you want the AC holding you back? maybe it's not even good for the AC compressor to spin at such high rpms so maybe the pcm is doing the AC as favor by shutting it down on hard accels.

 

Makes sense.. I'll have to play around with mine to see what rpm it shuts off at.