On the left side or pass. side of the motor up around the 2 back sparkplugs there is a conector/senser or somthing sticking out that looks like it at one time had somthing conected to it.maybe 2 wires.I've had this car a while and this is the first time i've been under it to inspect.I'm starting to prepare to drop the tranny(auto) out and put another used one in.while under there i've been finding little things that need fixing.Now the catty has been removed and the smog stuff to.The twin fans has one that runs when the key is turnned on and i've not run the car long enuff to ever see the other fan turn on.now from what i've read on here there is a second senser that tells the second fan to come on.I think this object is installed in the head.It's not the knoc senser.although that wire has been chewed in two.there is a wire hanging that looks like the connector for a v6 knoc senser that is a single wire.It night be for the o2 that dose not exsist because that part has been cut out.I would one day like to put this 89iroc back into it's stock condition.with very few upgrades.any chance the part in ? could be part of the cooling system.

 

The one in the head is the cooling fan switch. It has a connector that looks very similar to the knock sensor.

The O2 sensor is on the other side and has a completely different type of connector.

 

I thought that might be it.I'll need one of them some day to get my cooling system back to stock. thanks for the info.