Mechanics

DIAGNOSIS

1988 Cadillac Fleetwood

Air Conditioning problem
1988 Cadillac Fleetwood V8 Front Wheel Drive Automatic 110000 miles

My 1988 Fleetwood has an air conditioning problem. When it get cold the air conditioning quits working. I take it in and the GM dealer can't find any problem. When it get warm outside I take it in for repair and they just evacuate the system then recharge it and it starts working again. It will continue to work until it get cold outside again. Any ideas on what can be wrong? Is it possibly linked to some elctronic component or sensor?
AD
Avatar
Jrneaves
April 23, 2008.



Is this a manual or automatic system? My software shows both. So if it is cold out and you take it in, they top off the freon and it works?

Tiny
Jack42
Apr 24, 2008.
In response to the answer to the air conditioning question I submitted yesterday, the transmission is an automatic. And, they do not top off the air conditioning because none has leaked. They just evacuate the system and put the old stuff back in. It is not freon because the entire ac system was replaced and it uses the new coolant, what ever it is. They have dye tested the system and found no leaks. They have replaced the upper and lower sensors. All they ever do is evacuate the system and put the coolant back in, and it works until it gets cool outside again. Nothing is freezing. The place that does the diagnosis and repair is a GM dealership. The ac is under the Goodwrench warranty. I just don't think they know what to do. Their diagnostic procedures do not identify the problem. I am hoping an old time Cadillac mechanic has seen this problem and might know what causes it.

Tiny
Jrneaves
Apr 24, 2008.
Im well aware it is an automatic transmission. I asked if it had an automatic system (set desired temp and let it go) I was using freon as a name, it is 134a. I asked about the auto system because if it is colder outside than the desired setting it wont work. Ambient temp shouldnt effect the operation, If they cannot figure out where the a/c signal is stopping, then yes I would recommend another shop, preferrably a Caddy specialist

Tiny
Jack42
Apr 24, 2008.
I am sorry I misunderstood you. It is an auto temperature system. Now that it is warm again I guess I need to take it to the Cadillac dealer. The temperature control still works in that it heats up the car when the outside temperature is colder than the inside. However, the " service air conditioner" light comes on, and it goes to " Econ Mode" and will not allow the ac to start.

Thanks for the information. I will go to a Caddilac expert.

Tiny
Jrneaves
Apr 24, 2008.
You need to find out what code the AC is setting, thats why it goes to econ all caddies 89 and up do the same thing. Try going to autozone for the code im not real familer with 88's whats the motor size? 4.1 or 4.5 or 305 or 350 chevy?

Tiny
Buzzsaw
Apr 25, 2008.
The engine is 4.5.

Tiny
Jrneaves
Apr 26, 2008.
Is there a way for you to take a picture of your heater and AC controls. I need to see what it looks like

Tiny
Buzzsaw
Apr 26, 2008.
Here is a picture of the Cadillac temp control panel. You can see the Service Airconditioning" light lit.


http://www.2carpros.com/forum/automotive_pictures/182288_caddy_1.jpg


Tiny
Jrneaves
Apr 27, 2008.
I had a brainstorm to disconnect the battery and re-connect it to see if that reset the A/C controls. IT DID! Now, what does that tell us?
AD

Tiny
Jrneaves
Apr 27, 2008.
Try pushing off and warmer at the same time, with the key in the on position to see if it will go into diagnostics, it works with 89's and up to get codes

Tiny
Buzzsaw
Apr 27, 2008.
Page 1 of 2

AD