jeff968

A fellow 968er is having cooling issues with his 968. Any opinions would be greatly appreciated. Jeff

I bought my 968 in 2000 then had to replace the thermostat because the car was indicating it was overheating when it wasn’t. This spring, the cooling fan kept running (all night) after turning off the car and it was killing the battery. Again, replaced the thermostat. This week the car again indicated overheating and actually cut off I guess automatically when the gauge went into the red. The car wasn’t actually overheated. Had towed to the mechanic and he is again replacing the thermostat.

Tuesday evening, I don’t think the fan came on after I turned the car off after driving home in rush hour traffic like it usually does when the engine is hot after driving. Yesterday morning, on a cold engine start the car did not want to turn over like it had a weak battery. The battery and alternator are new and mechanic has confirmed nothing is wrong with either. Fifteen minutes and four miles later, while driving to work in slow city traffic once the engine heated up the temp gauge continued slightly into the red. The car has always run a little hot but in the past when it would get to the bottom of the red line I presume the fan kicks in and the engine temp gauge moves back down between the hashes. Yesterday, it went just slightly into the red, wiggled a round a little, then the “!” light came on and the engine cut off. I didn’t fool around, I just had it towed to a mechanic. I didn’t try to re-start it but when I turned the key to battery the “!” was still on about 5 minutes after the engine cut off. After towing, the mechanic told me that the car will cut off automatically if the gauge indicates an overheating. Not sure if that’s true of the 968 or not. When the mechanic started it at the shop (engine had been idle for 2 hours) the “!” light was not on anymore but the engine was also now cool. So far, he has replaced the thermostat and is looking for other electrical issues.

Several months ago a mechanic had replaced the battery and a thermostat or relay (or both, not sure) when the fan was staying on after the car was off and engine had cooled. That problem was obviously killing the battery but I’m wondering if this problem isn’t some related electrical issue. I think this may be my third thermostat and second in several months so I suspect the problem may be originating somewhere else. Thanks again for any ideas or help.

Miles968

If I recall there is a sending/control unit that is screwed into the radiator that controls the cooling fans. I am not sure it is your entire problem, but they are pretty cheap and easy to replace.

Best of luck and keep us posted

AZ968Cab

The fan will stay on after the car is turned-off relative the the temp. Mine does it for 5 min or so but I've never seen a battery issue as a result.

968workaholic

There is a thermo-switch on the radiator below the upper radiator hose that control the fan operation. If the switch goes bad either the fans will not come on at all or they will run after the car is turned off and kill the battery. It sounds like the situation is likely the water pump impeller seperated from the shaft

notthd

To me it does sound like the temp sensor unit. It dictates when the fans run. If it is giving false readings it can leave the fans on or off too long or not at all (simulating a thermostat not working). One thing to note is the fans will come on regardless of temp if the AC is engaged. If you are driving and it gets in the red hit it and see if it helps. If the fans come on at all the relay is fine. Also- Does the heat blow hot when it is overheating? If it is getting hot crank the heat and see if it takes any temp off the motor. If it does not or it blows cold the WP might be dead or there is air in the system. Last thing to do is see what the temps are actually- in the motor and in the radiator. I have a coolant post out there not too far back when I was looking for cooling issues. Mine was the WP.

Another thought is these cars are a bitch to get the air out. Performing the factory procedure with the front of the car elevated seems to help. Sometimes it takes more than one try to get it all out. If the thermostat overheated the car the first time, when it was replaced the system amy not have had all the air out. the Sensor in the radiator just below the top hose will not read properly if in air. Just a thought.

Here is the factory procedure- If you want to try replacing the sensor with a good one I have one you can use or buy... try it and send it back if it does not help, keep it if it does. Good luck.---------------two post in the same day with the same dwg- what are the odds. Feels good to be back after being away for a few weeks..Cheers, Mike