2001 Gt 5mt Cooling system question


New Member
Sep 1, 2004

Hey everyone, I have a question and need some guidance. I’m trying to figure out how hot a car I bought for my son should run.
I bought the car for my 18 yr old son a few months ago and drove it 2hours home with no issue. While I was teaching my son how to drive a stick (doing stop and starts in a parking lot) we had the A/C on the car overheated. Well, the needle never moved from the middle of the gauge (190ish degrees) but I know the gauges in these things dont measure true temp. While we were practicing the starts and stops i saw coolant squirting about from under the hood at the passenger rear area and we shut it down right away and had it towed to the AAA i run. One of the plastic connectors on a heater core hose broke. I replaced both hoses and did 2 cooling system flushes to try and clean all the rust and such out of the system.
I have since been driving the car back and forth to work (about 3 miles each way) with A/C on I have been monitoring the coolant temp with both Dash command app and FORScan app and while driving if just cruising and not shifting gears the temp stays around 210 degrees. If Idling it will sit and Idle forever and sit between 198 and 212 degrees. But if shifting gears and driving its been as high as 224. When the temp gets that high I have turned on the heat and opened windows and gotten temp back down so i dont know if it will go higher in temp….

I guess my question is what true temp should these things climb to safely? I have changed to a 180 high flow stat and added water wetter to the 50/50 mix of coolant and nothing has changed.

any reason to be concerned here? I haven’t wanted to let him drive his car because i dont want it overheating and breaking down on him. So I have been letting him drive my car instead. But i would really like to get him in his 2001 and get my 2021 Gt back from him! Lol
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Is the tstat opening up all the way? Once it gets hot it should gap open. How deep is it squirting into the passenger rear? Some say 180 tstat makes car run hotter, depends on how things are setup. My needle stays really steady too though, I think it's broken but I just replaced my sensor so I'm hoping it moves closer.
Quite a strange situation, because usually it's the opposite - the temp gets too high when idling as the radiator doesn't get air cooled. You should be fine if your car is running at anywhere between 190-220 degrees. Dumb question, but hows the oil level? Maybe there's not enough lubrication at higher rpm and thus the engine produces more heat.
A few good points have been made, I would recommend first making certain you have consistently good heat and second getting a scanner and seeing with the actual coolant temperature sensor is showing in the data stream. Manufacturers what engines to run at 220° for optimum efficiency and longevity and I think the fans don't come on till around 230°. Personally I would install a quality motorcraft 195 degree thermostat, verify the temps are staying around 220 in normal driving and you should be good to go.