View Full Version : a/c causing car to overheat

07-14-2007, 05:02 AM
My air conditioner only blows cold when I'm going at speeds of like 25 mph+... the faster I go, the colder it blows.

When I idle, luke warm air comes out.

Also, when the A/C does blow cold air ... the car overheats... to 7 out of the 8 bars for engine temp. The oil temp also goes up 100 degrees.

I tried doing a coolant flush to get rid of this problem... no luck.

Any idea(s) on what it sounds like it could be?

I have 35% tints and a full black interior... and in the 100 degree weather we've been having lately, I feel like I'm going to die!

07-30-2007, 07:45 AM
thermostat maybe ??

08-01-2007, 11:06 PM
I have the exactly same problem... the other day I was stuck in traffic and it started overheating.... I had to pull off to the side and turn off my car to let it cool down... Honestly I think that the fact that our fans are not electric has a lot to do with it. I feel as though our cars just weren't meant for hot places

08-05-2009, 07:45 PM
im having the exact same problem too, its been getting really hot here in nyc.

08-05-2009, 08:36 PM
I lived in phx with summer temps around 115 degrees never overheated once, but on your problem, sound like your not getting any air flow over the condenser and radiator. check for blockage like dirt/ debris

08-05-2009, 09:36 PM
when you turn the a/c on the high speed fan should come on in about 10sec-5sec make sure it's doing that also make sure you don't have any air bubbles in your system

08-05-2009, 09:49 PM
When you turn the A/C on, the electric fan should run on low speed constantly. It sounds like the electric cooling fan is not working. This would explain the overheating as well as the A/C not working unless you are moving (no flow across the A/C condenser). In traffic, if the temp gets high enough it should kick on to high speed too.

If the fan doesn't turn ever, it could be failure of the fan itself, fuse #42, or fuse #51, or wiring somewhere in the system. I think this failure is most likely given your description.

If the fan turns on low speed, but never high speed it could be failure of the 2nd speed cooling fan control relay or failure of both the A/C high pressure switch and the dual thermal fan switch, or wiring in the system. I think this failure doesn't fit the given symptoms as well as the previous (zero electric fan operation).

Just some ideas.

08-06-2009, 05:20 AM
It isn't the fans. Either you need a t-stat, or have a bubble in the system (a common B5 problem). Could also be a fan control module problem. And what was your pressure when you checked the freon/lube charge?

08-06-2009, 07:19 AM
to the op, does the temp come back to normal or less then normal on the high way? if thats the case then its your thermostat or water pump. if it never comes back down then you have an air pocket somewhere.

to the rest with ac problems, check the huge fuse behind the knee bolster.