Ok, is there 1 or 2? I get mixed answers, i only can find the one on the intake manifold. Also will putting pipe dope (thread sealer) on there mess anything up?

 

Not sure on your car, but it should be similar to the engine on mine. I have a 350 tpi, just below the throttle body is the coolant temp sensor, in the area near the #1 sparkplug is the engine temp sensor for the temperature guage on the instrument panel, near the starter is the temp sensor for the heavy duty fan relay. All three sensors have a different type connector and are not interchangeable. They all come with a thread sealer already applied.

The Trickster!!!!!!!!!!!!

 

ok thats what i needed to know, the one below the thorttle body is the one that sends the info to the ecm right? It doesnt look like it has thread sealer on it Wont hurt to put some on it will it?

 

On your '91 there are two coolant sensors. The one in the front center (under TB) of the intake manifold is a two wire unit for use by the ECM. Can dope it up all you want.

The gauge sensor is located in the front corner of the drivers side head. Sticks out at an angle and can be seen behind the A/C compressor. This is a one wire sensor and needs to be grounded to the head.

Fan is ECM controlled and has no sensor of it's own.

RBob.

 

Ok so since my guage works the #2 one isnt bad. But i dont even know if #1 is bad but i heard it wont throw a code and im well on my way to replacing every sensor for the engine