The weather is finally warming up in the Northeast. And lo and behold, I can't get cool air in the car. After testing several ideas, including the the A/C system which DOES NOT need recharged, I've come to the following conclusion and need some help.

The Air Temperature coming out the center top vent is about 5 degrees F warmer than the air Outside with the Air conditioner on and the Thermostat set all the way on COLD. <_<

If the engine is cold (ie- starting first thing in the morning, engine not up to temp yet...) the A/C works great, tons of cold Air...but once the engine has warmed up to temp, the air gets warm. After removing the Glove Box from the dash and the panels below it, I found the blower housing and the box it enters. This is apparently where the Heater Core and A/C Core are located. This is directly behind the radio console and beside the glove box. Near the floor towards the front of the car, the box gets warm to hot (apparently the heater core is inside here) and as you move towards the rear of the car, the box gets cold (apparently the A/C Core). Now as I rotate the thermostat in the dash, a little silvery pin rotates on a small box mounted on the heater/AC Core housing. I'm assuming this controls a "door" that switches between "Hot" and "Cold" air.

Now, my question is, since the heater core is still getting air into the car when the knob is set to "Cold", does this box need replaced, or simply adjusted? It appears you can manually move the silver pin with a screwdriver, though I haven't tried. Is there a valve to shut off the hot coolant to the heater core when turned to "cold" or is it always on?

Has anybody else had this problem? Is it easy to fix, or should I give up and take it to a dealer?

Thanks so much in advance for your help! :)

joc1394

Ok, after further investigation and tinkering...

The Little Box with the Silver Pin is moving as far as it will go when it is set to "Cold" with the thermostat control nob. I tried adjusting it with a screwdriver and forcing it to go further than it does right now and it will not budge. Apparently that part is working. Now i'm really starting to believe I have a valve somewhere that should be closing to shut off the engine coolant from going into the heater core. I have a friend with an Alero whom I plan on visiting to see if the heater core on their Alero warms up even when the A/C is running.

I'm really not looking forward to tearing the entire dash and air handler system apart myself to find the problem, I think if I find that the heater core isn't supposed to heat up when the A/C is on, I might just take it to a dealer, unless someone here has some insight.

Thanks again!

joc1394

Hi Joc,

I am having the similar problem with my 1989 Delta 88. The AC would blow cold air when I start the car but it gets warm after a while. In addition I also have some leakage of coolant on the floow when I turn the heater on. I was hoping to see a reply to your query :(
Can someone tell what is the solution to this problem?

thanks

If its not getting all the way cold it could be something as simple as the connectors not being all the way connected behind the console. I would take a look at that avenue before I would start tearing too much apart. I mean, its a 5 minute diagnostic...can't hurt

OK! Finally I once again have Ice Cold A/C!

I checked the connections, and all the actuators, everything appeared to be working properly, so I gave in and took it to my local garage. The diagnosis was as follows:

0.22 lbs of R-134a "compressible gas" was in the A/C system. out of the 1.53 or some odd pounds the system should contain. The rest either decomposed or leaked out. The funny part is, it pressure tested "OK" and they can't find a leak. The fix was a recovery of the existing gas, pressure/vacuum test, and a recharge. This totaled just over 50 bucks including dye to show future leaks. I'm happy (and cool) once again. I took it's "temperature" from the top center vent. A chilling 49 degrees F.

Oh, and thanks to "double0alero" for recommending gmpartsdirect.com in another topic. It was very useful for finding where some of the parts I checked were located and what they do.

Thanks,

joc1394