My car's (84 944) been running hot for a while .. it normally sits around the 3/4 line when I'm driving, and creeps up even higher in traffic or sitting still. I found out that the cooling fan relay was bad (didnt 'click' when power was sent across the relay). The big cooling fan never turned on. Dualblade and I pulled the relay yesterday and hooked up a switch to manually turn the fan on and off. This turns the fan on, however the car still doesnt seem to run any cooler. I know i still need a new relay, but im waiting to try to find one cheap from a part car or somewhere. However, I think something else must be wrong since the temp is still so high. The thermofan sensor is supposedly good, so im not sure where to look. I wasnt sure if maybe the thermostat is bad, or if i should drain and refill my cooling system (incase maybe proportions are bad or something), try adding "water wetter", etc... Any input would be great. Also, if u have or know where to get a working, cheap cooling fan relay (relay 1 in the early style cars) lemme know about that too. thx


-Scott

 

Did you do anything to the cooling system that seemed to cause this? IE this started happening the day after you drained/refilled the coolant to do something?

 

I had a similar problem, fans worked fine but the temp kept creeping up in traffic. Turned out to be a bad thermostat. I tried to see if there was air in the cooling system, which can be the cause of overheating sometimes, there's some detailed procedures on this forum, just do a search. You might want to try those techniques first since that will probably tell you if the thermostat is faulty.

 

Make sure the system is bled properly.

On my 951, it took me 30mins+ to COMPLETELY do the job. You have to wait/bled the system when the car is at operating temp (drive it for 15 mins or so) and let the fans come on/off a few times while bleeding the system (but in your case, do this when you get the relay, or turn them on using what you described and look at the temp gauge).

If this failes, could be that the thermostat is stuck.

 

bump

 

thermostat would be my first try. I've had thermostat problems before. Also, just get a new thermo fan switch, their like 15 bucks max, better then paying for a switch thats is questionalble on its integrity of a car its been on for who knows how long.
~Eyal