Northstar Engines and System Technical Discussion Discussion, 1996 Deville over heats when ac is on in Cadillac Engine Technical Discussion; Hi I have a 1997 cadillac deville and the temp begins to rise ONLY when the ac is turned on ...
Hi I have a 1997 cadillac deville and the temp begins to rise ONLY when the ac is turned on and it will only do that after driving for at least say 20 minutes or so. I really don't think the heads are blown because it only rises and overheats when the ac is turned on and there's no coolant coming out of the exhaust. Im trying to eliminate some possibilities and highlight some others and any help would be appreciated....
Automobile(s): 2002.5 F55 STS/64500mi, 2004 Ford F150 SuperCab4x4
MD Eastern Shore - Kent Island
Re: 1996 Deville over heats when ac is on
If you mean that coolant is mixed with the condensate from the A/C (drips out under the passenger's feet area) then you probably have a failing heater core......... OR one of the heater supply/return pipes across the right (rear, firewall) side of the engine is rusting out.