Very strange cooling fan issue
Mikey_P
07-31-2004, 12:13 PM
Got a '90 Cutlas Supreme with cooling fan issues.
The fans will come on when the AC is running, but will not come
on at all without the AC running. Changed the thermostat and the
sensor below the neck and that did not work. With the thermostat neck
off - coolant gushes out when you crank the engine over. I'm assuming
this eliminates a busted water pump but I could be wrong.
There were also two large cube-like things in the fenderwall fuse box. They were labeled as primary cooling fan and secondary cooling fan. Are these the actual relays or are they just fuses? I haven't replaced them but tried switching them around.
I'm not sure why the fans work with the AC but not under normal conditions. Are there more sensors? Computer bad? I'm stumped and
the local dealer has no diagnostic equipment for this car.
Please help.
The fans will come on when the AC is running, but will not come
on at all without the AC running. Changed the thermostat and the
sensor below the neck and that did not work. With the thermostat neck
off - coolant gushes out when you crank the engine over. I'm assuming
this eliminates a busted water pump but I could be wrong.
There were also two large cube-like things in the fenderwall fuse box. They were labeled as primary cooling fan and secondary cooling fan. Are these the actual relays or are they just fuses? I haven't replaced them but tried switching them around.
I'm not sure why the fans work with the AC but not under normal conditions. Are there more sensors? Computer bad? I'm stumped and
the local dealer has no diagnostic equipment for this car.
Please help.
spidervirus
08-01-2004, 09:37 AM
on your car one is supposed to work only when the car reaches a certain temp not all the time and the reason both come when your ac is on its designed to that to keep it from getting to hot to quick... if your car is not overheating i wouldn't worry about it
Mikey_P
08-01-2004, 10:38 AM
I did forget to mention that it is shutting off when the car gets hot. Usually it shuts off when the coolant temp is about 209-210 degrees. I
don't know if that's too hot to cause it to shut down, but that's always about where it shuts off. That's why I assumed the cooling fans.
We replaced the coil pack the other day cause we thought that was
originally the problem. And, after my first post, my uncle came in and hooked it up to an 'AutoXray' computer. But it says everything is fine.
Any ideas why it may be shutting off like this?
don't know if that's too hot to cause it to shut down, but that's always about where it shuts off. That's why I assumed the cooling fans.
We replaced the coil pack the other day cause we thought that was
originally the problem. And, after my first post, my uncle came in and hooked it up to an 'AutoXray' computer. But it says everything is fine.
Any ideas why it may be shutting off like this?
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