Overheating?

One more, I think I may have forgotten to mention: when it overheats, and I shut it down, the two fans stop also. I’d think the fans should still be running once the ignition is off for a while if the engine is hot but I don’t know...

Okay. So, I took it out today on a 5-mile run in city, country and fwy driving. The temperature stayed right at 190 (normal). It wasn’t until I got back home that it began to overheat (in the driveway, idling. On that 5-mile trip I drove it like I stole it).

The AC worked; the heat worked. The top and bottom radiator hoses were hot and firm.

Neither fan turned on until the temp gauge reached 2 lines past normal, then they both turned on high but couldn’t cool the engine down. I revved the engine to 35k RPMs which brought the temperature down to almost normal. While idling afterwards the temp gauge went back up in short time.

I’ve read these fans should kick on before it overheats and stay on afterwards (when the ignition is off to help cool the engine - this didn’t happen). I’m about to replace the fan control module, the radiator fan switch and the coolant temperature switch (all of which I’ve done before, which didn’t make a difference, using parts I’ve bought from Amazon at a fraction of the cost of OEM parts). The OEM parts are about $450 together, but I’m at my wits end. Am I being crazy? Replacing parts I already have? But, maybe I need to do OEM and it will solve all my problems? I’m stumped.

Thanks Joe! That is helpful!
The 8th letter on the VIN is an M.
Since I’ve replaced all those parts, how would I locate a bad sensor? I’m good with nuts and bolts but multimeters have always been a mystery to me...

Hi Joe. Hard to say about fans cause I’m just going by the temp gauge inside the car. The fans come on when the needle reaches almost two lines above the middle 190 mark. And as for that sensor, in the radiator, I’ve switched that out already with no difference (along with the fan control module).

Oh, sorry. Yes, the sensor in the radiator and the one I think you’re talking about (in the hose near the block which sends info to the gauge in the dash of the car) have both been replaced.

And got it. The issue with the fans turning on is that they don’t turn on until the engine has already begun to over heat, and at that point can’t cool it down. Also, they turn off when I turn off the ignition, even if the engine is at an over heated state (I’ve heard they are suppose to continue until the engine cools down when car is off).

Thanks Joe. Never heard of a dealer computer update for these cars.

Thanks Joe.