Help. please. Lacrosse engine fans keep running with high temp warning.


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Buick Ownership
I have this same problem however it only happens when it is cool outside. Like 50 degrees once the outside temp is higher it goes away?
I always have the exact same problem as this in WINTER. Trmperature guage pegged down to cold, fans running continuously, engine code light on😡 and in this case is that totally asinine block heater thermostat. It prevents the block heater from coming on unless it is -18C or 0F or colder and I chopped that garbage off! It was about -15C and I plugged in, Bing on comes the light, temp guage showing very cold and fans running non stop while driving. First thing I thought is a bad sensor or worse wiring etc. after all it is a POS Buick👎. Tests revealed correct coolant temp, properly functioning sensor and a call to the local Pewick dealer where I was asked if my block heater cord is damaged? I said what does this have to do with the price of rice in China? The car runs fine except for the above mentioned. Again the block heater mentioned and then I was told about the engine off timer, engine coolant being warmer than it should for being of for X amount of hours, and of course the intake air temp being above -18. The ECM thinks the engine is overheating and trips a code and runs the engine in preservation mode😡. Yes it is now spring and this is yet another thing to keep in mind having the identical symptoms mentioned as earlier. When I drive a GM product I always bring my code reader along!


I am having the same problem with my 2010 LaCrosse: The coolant gauge goes to zero, a message pops up that says the AC is stopped because of high engine temperature and the radiator fan runs for 10 minutes when I shut off the engine. There is nothing wrong with the cooling system. After a few engine starts, it will also pop on the check engine light. After usually 2 days, the problem simply disappears. Then after about 2 to 3 weeks it starts all over again.
And yes, I have replaced the coolant temperature sensor (incidentally, very easy and inexpensive to do).
Anybody know what's going on here?
Did you keep driving the car?And if yes for how long it just popped up on my car yesterday.


New member
Buick Ownership
Have a 2012 lacrosse with a 3.6 l same issue
Temp gauge cold a\c off ECU thinks engine is hot! Has the p0128 code
Any fix on this yet


New member
Buick Ownership
2011 LaCrosse CXL
This happened to my LaCrosse twice. Once was a bad water pump seal and the second time was a bad water pump.


I've had that problem myself.
I have a 2008 Buick LaCrosse Super, 5.3L V8. While I love the feel of my LS4, I hate the problems it causes me. When I first got my car, I had to replace wheel bearings, hub assembly’s, front right stabilizer link, starter, battery, starter and ignition relays, a transmission service, and now a timing chain. Well, my car was down for about two months and I finally got my car back up and running for about a day. On my way home, a message on my car appeared “A/C off for engine protection”. I didn’t think too much of it at the moment since I had just got my car running again. Well, the next morning I hop in my car to drive home and realize the message was displayed again. I pulled into my driveway and left my car idling because I was about to jump my moms car off, and about 5 or so minutes go by and white smoke started coming from under the hood and my coolant was bubbling. I immediately shut my car off, but even after shutting it off the coolant was still bubbling. I waited for it to cool down, and after looking at it, I noticed coolant had bubbles out onto my strut tower and many other places, but my temperature gauges never read above the halfway mark. Online it says it could be a stuck open thermostat or that I need a new seal on my piston rings, or a blown head gasket or cracked cylinder head. I’m not sure which, but I’m tired of replacing parts after parts, I shouldn’t have to be dealing with all of this at 16 and replacing these kinds of things at 158k.


For the second time in eight months, when I started my 3.0 Buick Lacrosse, a warning stating that the AC is shut down due to engine overheating and also both fans will not stop running, even when I shut the car off, for at least 10 minutes. The strange thing is that the temperature guage stays at full cold along with the engine actually being too cold instead of too hot....even after running the car around town...and a code for Engine UNDER temperature(due to the fans never shutting off the whole time) is stored......AND the air conditioner actually does work just fine. Anyone ever have this happen to them or can share what detective part is causing this?
What mine does The AC actually shut off
The warning says AC shut off due to heated engine, the temperature gauge is at cold
Other words it stop working
When I shut the car off the fan still is running
As I checked on it 5 min later the fans shut off
I’ll go back after 30 min of being of and try it again hopefully the problem will cease
I’ll let you know
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