I have a 87' 2.8 V6 camaro the coolant light does not come on I replaced the bulb in the dash panel (which was blown) and the 2 wire coolant temp sensor and the light still does not come on during the system check. It does come on when you start the car...does the V6 have a 1 wire temp sending unit?

 

Sounds like a dummy light cluster? The 2 wire temp sensor is for the ECM, under the throttle body.

You want to replace the 1 wire sensor in the front of the drivers side head. Should have green wire with white stripe.

99% sure on that BUT I dont have the dummy light cluster, though it is a 2.8.

 

Yes it is a dummy cluster...I will look for the 1 wire sensor so far I haven't been able to find it. Thanks

 

Found the temp sender behind the ac compressor...Do you need to take the ac compressor and bracket off to replace the temp sender? Looks hard to get too otherwise

 

It would probably be easiest, but I deleted my AC so I wouldn't know the difference between either method.

 

On my 89 its a solid green wire.
I got it out with the A/C there, but it would be easiest to unbolt the entire A/C bracket and let it slide out and sit there.

 

I replaced the temp sensor and the coolant light still does not come on...it does come on when you ground the green wire. The wire does get almost 12v when you turn the ignition to test position

I'm wondering if there could be a grounding issue with the green wire? If so where? The other 2 gauges work normally...what's next?

I'm trying to get this fixed so the cooling fan will cycle on normally. I have it wired to a switch for now

 

The 'idiot light' will not come on during normal operation until there is temperature issue way past 'you're screwed' (258°f). It will light during crank for 'bulb test' (or peg gauge hot if you had one).

The fan will run at roughly 220°f or with a/c on. If the ecm faults, there is a redundant fan switch that turns the fan on at 238°f.

Make sure the fan/relay work first.

 

I replaced the fan relay, temp switch for ECM, temp sensor for fan...the coolant light will come on if you ground it during the bulb test but still doesn't come on at bulb test withe the new sensor

That's why I wonder if there could be a grounding issue maybe at the ECM, the ac compressor isn't kicking on either. From what I've learned it's the temp sensor that allows the cooling fan to come on if it's not working right the fan will not come on and if your not getting a coolant light at bulb check it's not working right. I know they bulb is good I replaced it and the light will come on when you turn the ignition to start the car

 

The bulb (aka : 'idiot light') is a separate circuit from the fan switch (redundant fan control) or, the ecm temp sensor.

If the light doesn't come on during crank (starting the engine), there is a problem with the ign switch.

Regardless of the 'idiot light' working, it has zero influence on fan operation.

The 'idiot light' should never be on unless you're starting (bulb test/crank) the engine or, the coolant temp is way past good for anything.

If you a/c doesn't work (low/no charge)... the fan wont work as well

 

I will plug the original fan plug back in and see if it will cycle on with a new temp sensor. I figure it should kick on shortly after the thermostat opens...I'll have to learn how to troubleshoot the AC compressor it doesn't seem to be getting voltage to the 2 ac compressor wires

 

IIRC 218°. Stock thermostat is 195°. The idiot light only comes on on bulb test/cranking OR if its dangerously overheating.

The stock temps for the original cooling system are retarded and only for emissions.