Hi im new to writting forums so please do bear with me. Im after some advice regards to my engine compartment fan on my 997, when i first start the car from cold everything is all good both water temp rises to the correct temp followed by the oil temp a few miles later however when the oil temp hits 90 degrees my engine fan comes on and wont go off no matter how steady you drive, ive tried driving for miles on a straight roads to try and see if i can cool the engine a bit but it just wont go off, both temperature gauges dont move once its warm so i dont think its over heating, i ordered a new engine compartment sensor and fitted that earlier but its still the same, i was wondering if anybody had any solutions or is it best to take it straight to the dealer.
Thanks for any respones in advance.

 

Sounds like one of your radiators might be out. Does your air conditioner cycle to not so cold air when your temps get higher?

 

Hi White Rock, thanks for the reply, my aircon seems ok and the two radiators at the front come on when the water temp rises and then goes off after a while (if the aircon is off) when the temp drops, ive also noticed since i posted the thread that even if i go out to the car after its been parked up for an hour or so and the oil temp is down that the engine fan still comes on as soon as you start it, its running at full speed too its already had the fuse pulled at some stage before i had the car to stop it coming on at slow speed at all times, im confussed, the only time the fan doesnt come on is if its been standing over night then as i said in the first thread it comes on when the oil temp hits 90 degrees and then wont go off.

 

I believe the "engine fan" (the one in the rear deck) works to cool the engine compartment, and is triggered by engine compartment temperature, not oil temperature. If the engine compartment is hot, it will come on even when the engine is off. After your drive, when you stop and shut off the engine, does the fan go off as well? Or does it continue to run for a while? If the fan continue to run, it sounds like you may have something blocking the normal airflow into the engine compartment, or perhaps a panel missing that directs air to the engine compartment during normal driving. Check under the car to see if everything is in place there. If the fan does shut off when the engine does, then I'd start looking for an electrical or electronic control problem with the fan circuit. The fact that the fan starts up right away after the car has sat for an hour or so points me in the latter direction. Good luck!

 

fgv1it is correct that the fan will kick on when the engine compartment temperature >176°F or the coolant temperature is >216°F. Either way, mine has never come on that I'm aware of. No reason to worry unless your car is overheating.

 

My engine fan only comes on about 10 minutes after the car has been shutdown after about 30 minutes of highway driving in 100 degree temps and parked in the closed garage. It has never come on while driving even on the hottest of Texas days.

 

Thanks for the info fg1, the fan shuts off when i turn the car off and doesnt come on again untill i start it, im thinking i might put a thermometer in there and see what temperature the engine compartment is getting to.

 

Hey! Did you ever figure this out? Having the same issue dead on.

 

Hope he figured it out…he hasn’t posted in 12 years. Doubt he has the car.

 

I had a similar issue on my 997 4s. Turned out one of the radiators was out.