My 1999 STS is running very hot. But the thing is it only runs hot at stop lights. If Ikeptp it about 2200 RPM, it doesn't run hot. I'm told that is not a head gasket problem. Can anyone help?
Normal operating temp is anywhere near 188-224, since 188 is when your thermostat starts opening up and 224 is when the fan goes on slow. 228 is in a bit of a high side, try cleaning up the bugs and road grime stuck in the fins of the condenser/radiator with compressed air. Top radiator cover, the bottom splash shield and the flaps around the radiator are required since it will direct all the frontal air flow through the condenser/radiator rather than going around it. See if both fans are correctly working, they both should start turning slow when the temp hits 222-224.
Thanks, I will do that. It only hits 228 when parked and idling (which I do not let it do much of) but then drops back to 225 or 226 then back up, etc.
I say 205-215 because that is what I observed for for many years on my digidash '97. A consistent 205 in the summer to 215 in the winter. That said, 12:00 = 188-215.
The previous questioning posts refer to earlier deleted posts containing trolling and insults to members. Posted insults are cause for infraction and may lead to a temporary or permanent ban.
Please stay on topic and leave the personal pot shots out of CF. Thanks.
I also own a 99 sts (157,000 miles) and am having a cooling problem - there are so many threads about it on here its hard to find a good one. This one was pretty helpful so far so here goes:
When it is really hot outside, 90+ degrees, and when idling in stop-and-go traffic, the temperature gage will tick half a notch past vertical, normal operating temp. You can also start to smell that sweet cooked-coolant smell. Once I start moving again, the temp goes back to normal. It has been doing this the past three summers I have owned it, and it has never heated more than one notch past normal temp. On long highway trips, it never heats up.
The past two days, it started doing this when the weather was cooler, 70-75 degrees outside. I'm now a bit worried...
So after reading this post, I checked my purge line and it is flowing coolant just fine. The water pump is turning and the belt is in good shape and taut.
I did notice the upper cooling hose from the pump to the top of the radiator was hanging below it's normal place and was touching the water pump tensioner pulley. The hose is worn through the outer layer and will be replaced asap, but it still holds water with no leaks. The coolant reservoir stays full.
I then let the car warm up to operating temp, and revved it until the temp ticked over. I noticed both fans stay off completely until the temp ticked over half a notch. They then both came on at full speed, and once the temp went back down both shut off again. I let it warm up again and the same thing happened.
So, is this fan operation normal? The fuses looked ok. It doesn't seem right for a car to start to overheat before the fans kick on.
Should I be worried or am I over-reacting? Beginning stages of HG failure?
Other things to note, the car has DEX-Cool in it, and one year ago it was leaking coolant (1-1.5 liters a week) so I added some radiator stop-leak. It hasn't leaked coolant since.
Sorry for the novel, but any advice would be appreciated.
Well ok then, I'll just keep an eye on it I guess.
Thanks!
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Related Threads
?
?
?
?
?
Cadillac Owners Forum
4.8M posts
369.7K members
Since 2002
Cadillac Forums is the perfect place to go to talk about your favorite Caddys including the ATS, CTS, SRX, Escalade, LYRIQ, Vistiq, concept and future Cadillac models.