944 keeps running hot - help!

[rlrgirl04]

I have a 1983 944, 5spd, non turbo. I have replaced the thermostat, water pump, radiator, and lower radiator hose. All are from Porsche. The shop I took it to for the water pump said the fan was not working due to the logic module??? so they direct wired it to work when the car is running. Now, it's still running hot - between the 1/2 way point to the edge of the orange area and the fog lights are not working (they were before they messed with the wiring). Any ideas?

Thanks!

[ronin]

the logic unit, eh?

snapperheads should have checked the fan switch or relays first. check to see if you have coolant mixing with your oil or vice versa. we'll go from there

get them to wire things back the way they should be and find someone in your area that actually knows Porsches. depending on where you are, I may be able to make a recommendation

[rlrgirl04]

I think they were just lazy and wanted to charge me more $$$. It was a $900 bill when all was said and done.

I am just west of Orlando. Any recommendations that won't want my bank account as well and knows what they are doing?

Urgh!!!

[ronin]

if you're willing to make the trip, I have a friend out in Viera by Cannon Beach with an expert shop. that's not too far from you. he will definitely take good care of you, and actually knows what he's doing! Porsches are all they do

[rlrgirl04]

Viera is quite a trip, I would be scared to drive it that far in it's current condition. But thanks for the suggestion! I did find a guy local in Longwood that races 944's in the SCCA. I'd probably rather take it to them instead of trusting that same shop to put it back the way it was lol.

I read somewhere else that the radiator needs to be bled and it mentioned a 'switch' on the upper hose to bleed it. I don't have that on mine. Should I change the hose? Is it possible that that could be the problem?

Thank you so much for the help so far!

[Techno Duck]

On the top of the block where the upper radiator hose connects, there is a 13mm bleed screw. Get the front end of the car as high as possible. Let the car get up to temp, turn heat on max. Open the bleed screw until you get a solid stream of coolant.

[JivenJim]

Might try replacing or have a Radiator Shop Core your Radiator. Or Drop it in a big bath of CLR. I think it was about $75 to have mine cored (cleaned internal)

[hpservertech]

Do the early cars have a temp sensor like the late cars? If so it doesn't sound like that has been replaced yet.

[rlrgirl04]

Thank you Techno Duck! I could not find that info anywhere!!!

Radiator is new, so I know that's ok.

I was thinking about the temp sensor. That'll be my next investment if the bleeding doesn't work.

Thank you everyone for all of the suggestions!

[earlr85944]

Check the strength of the antifreeze, they sell the gauge at any auto parts store.

Also is the car showing signs of running hot? Do both fans run? With a new radiator verify the fan switch is also new. The temp switch could be giving a false high reading, check and clean the gounds on the car, mostly the ground right off the battery and from and to the engine. Water wetter also helps....

[hpservertech]

Early cars dont have the dual cooling fans.

[Lizard944]

If you recently changed the thermostat and now you're having trouble, I'd say it's probably the new thermostat. You really have to check them closely before installing. I bought one from the dealership and it didn't begin to open until after 200F. Should be pretty much fully open at 180F
Thought it would be ok after I installed it, but sure enough it ran in the upper 1/3 of the temp gauge. Removed and replaced with the older one that I had just removed (tested good....opened at ~180F), and everything was fine again. Porsche seems to have occasional quality control issues with these.

[earlr85944]

early cars have dual fans, they each have 3 blades though

[hpservertech]

I stand corrected.

[floorboard]

I have an 83 944 also, The guy that *fixed* it put a new boot on mine, but forgot to plug in one little sensor wire that goes to the fan, I took it to Tucson and thought it was gonna melt, so I took it back to him and hes like oh heres your problem, then he plugged it back in and now its back to running nice and cool, take a look miss, see if one little wire is hanging loose and plug it back into your fan.

[floorboard]

fan housing, that is

[JonA]

Make sure your cooling fans aren't running backwards. If the "professionals" got the polarity wrong they will run backwards and try to push air out the front of the vehicle.
Does the heater work? unless the air is bled out properly the heater will not blow hot air.

Jon

[rlrgirl04]

Ok. I bled the radiator, checked the new thermostat, the cooling switch is good, the fans are blowing right. I can't find where the temp sensor is (is there one?). I have ordered a new coolant reservoir cap from Porsche (it's still the original cap) thinking maybe I don't have enough pressure to push coolant through the engine.

Any other ideas? Oil is fine... Urgh!!!!

[legoland951]

The idiots probably wired the positive into the fan. These cooling fans are negatively triggered, meaning when the coolant is hot, the fans get grounded and turns. When you apply positive instead, the fans turn in reverse. There is no "logic unit" but I think those guys need a logic unit in their head. There is a fan relay and a thermostatic fan switch on the driver side top of the radiator. Its directly under the upper radiator hose and its a cheap unit (around $10) which cause 75 percent of fans not working.

[legoland951]

If the fans are in the proper direction, check the actual coolant temperature with a thermometer (I normally squeeze the upper hose with thick gloves and if its pressurized, its probably hot). Sometimes, its just the block temperature sensor that is off and not reading temp correctly.