Cooling fan issues - please help
#1
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I apologize, I have searched and still do not know what to look for to fix this.
At road speed, the car cools fine (needle right in the middle), but the needle rises quickly the minute I get into the driveway. After shutting the car off, the fan on the passenger side will continue to run for several minutes, but the
driver's side one does not. Also it appears to run at the "slow" speed - compared to my 944 N/A where both run at high speed for a lot shorter period of time. The driver's side fan also does not run when the ignition is switched on.
The fuses are good. I have swapped the relays on the two cars so this is not the culprit.
What else might be the cause of this problem?
EDIT: I just checked and when the A/C is on, only the passenger fan comes on (while both on my 944 N/A come on). Starting to seem like an electrical issue with the fan... Any thoughts?
Note: I just changed the coolant and rad hoses on my 951 (I have bled it several times and will continue to do so for a while to make sure that there are no air pockets).
At road speed, the car cools fine (needle right in the middle), but the needle rises quickly the minute I get into the driveway. After shutting the car off, the fan on the passenger side will continue to run for several minutes, but the
driver's side one does not. Also it appears to run at the "slow" speed - compared to my 944 N/A where both run at high speed for a lot shorter period of time. The driver's side fan also does not run when the ignition is switched on.
The fuses are good. I have swapped the relays on the two cars so this is not the culprit.
What else might be the cause of this problem?
EDIT: I just checked and when the A/C is on, only the passenger fan comes on (while both on my 944 N/A come on). Starting to seem like an electrical issue with the fan... Any thoughts?
Note: I just changed the coolant and rad hoses on my 951 (I have bled it several times and will continue to do so for a while to make sure that there are no air pockets).
Last edited by fbgh2o; 04-26-2008 at 09:31 PM. Reason: Additional diagnosis
#2
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My car also gets hotter when its idling, but not in a concerning way.
I think one of the fans is thermo-electric, so only comes on at certain engine temps and shut down. At one time one of my fans wasn't coming on at all - needed a new switch and its was fine. My mechanic did the work - from memory fitting the switch required draining the coolant.
I'm no mechanic, so hopefully one of the more knowledgeable guys will chime in.
I think one of the fans is thermo-electric, so only comes on at certain engine temps and shut down. At one time one of my fans wasn't coming on at all - needed a new switch and its was fine. My mechanic did the work - from memory fitting the switch required draining the coolant.
I'm no mechanic, so hopefully one of the more knowledgeable guys will chime in.
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I have been through Clarke's. I think it is the resistor wiring for the driver's side fan.
I can jumper the fans to run at high speed, but the driver's side one will not run when jumpered (passenger side one does). However, the fan itself checks out okay.
I am going to order a new thermo switch - the lower temperature one (85C/93C) ... just in case it is that (even though the switch appears to operate to bring the fans on at low speed).
I can jumper the fans to run at high speed, but the driver's side one will not run when jumpered (passenger side one does). However, the fan itself checks out okay.
I am going to order a new thermo switch - the lower temperature one (85C/93C) ... just in case it is that (even though the switch appears to operate to bring the fans on at low speed).
#6
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Thanks for the advice. Bad wiring proved to be part of the problem.
I rewired the resistors and nothing changed. Just out of chance I reswapped the relays and behold everything works... Must have been a bad relay and the wiring... In any case, it all works now and I can drive the car
I rewired the resistors and nothing changed. Just out of chance I reswapped the relays and behold everything works... Must have been a bad relay and the wiring... In any case, it all works now and I can drive the car
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