Radiator fan runs all the time

ROCKYFPD

MEMBER
2001 PONTIAC FIREBIRD
6 CYL
2WD
AUTOMATIC
173,000 MILES

I have a 2001 Pontiac Firebird with a 3800 series 2 V6 engine. The cooling fans started running constantly and the temperature gage won't go up to the lowest mark. I checked the system pressure, good, the coolant level, good, and the fan relays, also good. The engine isn't overheating, but it really bothers me. Just wondering if the problem may involve the temperature sending unit? I'm not even sure if it would be the coolant temperature sensor or the engine temperature sensor, or if they are the same, or where they are located. Any help would be appreciated.

1 Reply

KASEKENNY

MECHANIC
18,907 POSTS

Yes. This very well could be the temperature sensor. So, we need to start with checking the resistance across the sensor and make sure it is not an open circuit.

https://www.2carpros.com/articles/how-to-use-a-voltmeter

Then we need to check the voltage as the engine warms up. If it doesn't change then you need to replace the sensor.

I attached the wiring diagrams below. Please run through this and report back what you find.

https://www.2carpros.com/articles/how-to-check-wiring

Assuming the temperature sensor is the issue I attached the process on how to replace it.

Let me know what questions you have and what you find.

Thanks

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