I am new to this forum. I have a 94 Mustang GT, 5.0L with some cooling fan issues.
Initial Problems: The Cooling Fan was failing to turn on when the engine was hot causing an overheat condition. This was an intermittent problem. I discovered the cooling fan pigtail ground was melted. Replace the pig tail, problem solved temporarily. Car is overheating again because the fan doesn't turn on when the engine is hot, but pigtail looks new still.
I have replaced the Coolant Temperature Sensor (is there a requirement to purge the air out of that fitting when changing the sensor)? I have now have a check engine light that turns on solid with the fan, and turns off when the fan stops. The car was running an aftermarket temperature guage. I have attempted to replace the factory temperature sensor that feeds the guage based on the advice of a Ford Mechanic. The factory gauge is not serviceable, likley why the car was running an aftermarket gauge.
The Cooling Fan now turns on a few seconds after I start the car and runs when the car is cold. It does cycle off eventually, and I still have this check engine light turning on and off with the fan (solid light, no flashing).
A KOEO test functions that fan properly. There is a code 118 - Engine Coolant Temp Sensor over max voltage, which appears to be connected to my overheating issues. I also have a 212 Sprout circuit ground, which I believe was connected to a TFI problem - no spark. I replaced the TFI module, that problem is fixed.
Any idea why my fan seems to run when the engine is cold and is throwing a check engine light?
The Car runs a little rich at idle, but otherwise starts and drives fine.
Initial Problems: The Cooling Fan was failing to turn on when the engine was hot causing an overheat condition. This was an intermittent problem. I discovered the cooling fan pigtail ground was melted. Replace the pig tail, problem solved temporarily. Car is overheating again because the fan doesn't turn on when the engine is hot, but pigtail looks new still.
I have replaced the Coolant Temperature Sensor (is there a requirement to purge the air out of that fitting when changing the sensor)? I have now have a check engine light that turns on solid with the fan, and turns off when the fan stops. The car was running an aftermarket temperature guage. I have attempted to replace the factory temperature sensor that feeds the guage based on the advice of a Ford Mechanic. The factory gauge is not serviceable, likley why the car was running an aftermarket gauge.
The Cooling Fan now turns on a few seconds after I start the car and runs when the car is cold. It does cycle off eventually, and I still have this check engine light turning on and off with the fan (solid light, no flashing).
A KOEO test functions that fan properly. There is a code 118 - Engine Coolant Temp Sensor over max voltage, which appears to be connected to my overheating issues. I also have a 212 Sprout circuit ground, which I believe was connected to a TFI problem - no spark. I replaced the TFI module, that problem is fixed.
Any idea why my fan seems to run when the engine is cold and is throwing a check engine light?
The Car runs a little rich at idle, but otherwise starts and drives fine.
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