Porsche8777

I am having problems with the operation of the cooling fans on my '83 944. First here is what has been done to the system. New radiator and temperature switch by PO 10k miles ago, new temperature switche yesterday, all new hoses, new reservoir, new water pump and thermostat (as well as belts, rollers, seals, and needless to say coolant change), replaced oil cooler seals. The car seems to do fine on the highway and the temp indicates about midway. In traffic with a lot of time stopped(I do live in Atlanta) the temp rises almost to the start of the solid block on the right or hot side of the gauge. Both fans then come on and the temperature drops back to the mid-range and the fans shut off, this is without the air conditioner on. When the fans shut off the left fan shuts down about 2 seconds before the right but both come on at the same time. When I remove the wires from the temperature switch and short them with a jumper the left fan comes on and the right does not, this is with the key in the off position. The wiring diagram in the Hayes manual is all but worthless in this area. Any suggestions on what to check or change next?

Matt O.

You said you replaced the temp sending unit twice?

It sounds like you're replaced everything that one would replace. My advice, call Partsheaven (http://www.partsheaven.com) and get yourself some used fans. They have a 3 month warranty, so they will work when you get them or you just send them back. I got some, and aside from the fact that a few blades were hitting the shrowd (I just shaved it down) they work.

At $35/fan you don't want to take the chance of screwing something up because your car overheated. Better safe then sorry. Two fans, $70, engine destroyed from overheating, $3500.

I'm sure there are other things, so people chime in here whenever.

-Matt

EDIT:
Also, there may be air in the system. Follow the instructions found at <a href="http://garage.type944.com" target="_blank">http://garage.type944.com</a> and vent the cooling system.