Hi everyone

Ok - this is probably the dumbest question, but I'm trying to locate the temperature sensor that activates the cooling fan on my 1989 Firebird 305 TBI. The car overheated today and the fan didn't come on at all so I guess the sensor is fried.

The Haynes manual says that V8 cars have the sensor located on the front of the left hand head, but the only sensor I can find is actually screwed in on the front right hand side, just off centre and in front of the throttle body.

Any help would be much appreciated

- by the way - the fan doesn't come on when I switch on the air con either - I noticed this mentioned in the FAQs - does this mean it's a relay rather than the sensor? If so, any ideas where the relay is located - the Haynes manual is no use at all

 

Well first of all your going to have to follow the wires coming out of the fan to find anything. I installed a fan switch into my 89 305 TBI and my car ran hot because the stock fan switch wasnt even connected. It is going to be closer to the back by the starter. It is a real pain in the *** to get to so that you can put the switch in but it is well worth the money and the work my car doesnt go a bit over 180 on my gauges. That is of course with a 160* stat but to answer the question it is closer to the fire wall by the starter. Good luck and tell me how it goes?

 

it is going to not be the one thats screwed into the driver side head, usually the fan one is in the intake manifold or in the thermostat housing,
the one in the head is the temp sending unit for the guages, single dark green wire

good luck

 

Probably NOT the sensor, suspect the fan relay(a big problem with these cars) or the fan motor or supply voltage to it.

 

Thanks everyone

It was the fan relay.

Once I found it, I took the cover off it and cleaned the burnt out contacts on the relay. It now all works again. I've ordered a new relay but the old one works again for now