Car overheats with A/C on


Old 07-12-02, 05:33 PM
Visiting Guest
Posts: n/a
Unhappy Car overheats with A/C on

Maybe someone out there has some ideas...

1992 Dodge Dynasty
3.3 Liter V6
206,000 Miles (Just can't kill this thing! )

Had overheating problems last winter. Replaced water pump, radiator and cap, thermostat, hoses and had system flushed. Problem was solved... or so I thought.

Now that summer has finally arrived, I can't turn on the A/C without fear of overheating. On a warm day (below 80 degrees), the car will run hot, but not overheat unless I pull a long hill or drive at extended high speeds (65 - 70 mph). On a hot day anything over 45 mph or a hill and the needle will get in the red, and then I have to shut the A/C compressor off and turn the heat on full blast to get the temp down.

Strange thing is, I thought most cars would typically overheat while idling for extended periods of time on a hot day with the A/C on. My car will idle all day with the A/C on in 100 degree weather!

The only thing I have not replaced in the entire cooling system that I can think of is the electric fan, wich I tested and works just fine (goes round and round ).

Any help here would be greatly apreciated
Sponsored Links
Old 07-12-02, 05:47 PM
Join Date: Jun 2002
Location: Long Island, NY
Posts: 1,531
Received 0 Votes on 0 Posts
Sounds like not enough cooling capacity. Did you use OEM or aftermarket rad?

Old 07-12-02, 06:11 PM
Visiting Guest
Posts: n/a
A/c overheats

Ya know, that never occured to me. I just whent to the local autoparts store and asked for a radiator for my make and model car assuming that I was given the proper part.

I'm going to look into that. Sometimes it takes another person to point out the obvious.

Thank you!!!
Old 07-12-02, 07:42 PM
Visiting Guest
Posts: n/a
Do the fans come on when they are supposed to? You state it runs (the fan) but does it come on when it should?
Old 07-12-02, 11:09 PM
telco tech
Visiting Guest
Posts: n/a
I'd think that at 60-70 mph, it should cool. I wonder about the antifreeze/water ratio. I believe the antifreeze does a poor job of transfering heat, too much antifreeze can cause overheats. Maybe no more than 50% antifreeze 50% water is a good start. Seen folks add and add antifreeze to their system until it just overheats even though the radiator is full and fan is working.
Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off

Thread Tools
Search this Thread
Ask a Question
Question Title: