1990 firebird cant find cooling fan switch wire .. dont know the color of the wire im looking for or where to find it

This is for the manual controls and not the automatic. If you need the automatic, let me know

Most of those year GM motors re-learn the idle settings automatically when driving above 35 MPH...be sure to clean or replace the Idle Air Control Valve...very critical in smoothing out the Idle...Hope this helps.

88? ,very old
what engine?
1.5 L EW5 (DA2)
1.6 L ZC(DA1 & DA3)
1.6 L D16A1 (DA1 & DA3) my guess, is the RAD fans dont turn on as the FSM directs?
and enging cooling question.
the fan is control by a relay and the cooling fan thermo switch
the relay white wire goes to the termo switch
the switch ground this white wire to activate the fan.
find.. i dont have the fsm only schematics.
the switch can only be 2 places on all car. in the RAD tank(look)
or on the water jackets of the engine.
my guess? see front of engine, front is #1 cylinder.
see main thermostat housing at 10pm?
to the right are 2 sensors, the one with a single with wire. bingo.
i see 2 ,secrewed in to cyl. head, there.

cooling fan relay is under radiator drivers side frame rail, square flat relay with 3 wires going to it is hard to see

I would use a 'fuse tester' that will light up if the ignition is on and the fuse is bad, while installed in the fuse block.

Otherwise, you can individually pull out each fuse and look at each one physically to see if there is a blown one.

Sometimes, there are 'fusible links' which come off of the starter which are multi colored and will 'stretch' when pulled on with about 5 lbs. of pulling force. When you find a 'stretchy' wire near the starter, it means the fusible link blew on it (like a fuse would blow).

If the DIC says cooling fan fault, it detected an open in the system somewhere.

You may need a ignition switch.Check the battery to make sure it is good,look to see that the wire for the solenoid ,the purple one is on the correct terminal,and that all the wires on the solenoid switch large post where put back on,check the fusible links on the large post connection are not burned into,if this was helpful,please rate,thank you.

SOUND LIKE FAULTY IDLE SPEED CONTROL OR FAULTY FUEL INJECTOR OR A INTAKE VACUUM LEAK.IF GETTING HOT WHILE STOPPING.CHECK COOLANT FAN FUSE AND RELAY.IF BOTH GOOD.HOT WIRE COOLING FAN TO CAR BATTERY USING JUMPER WIRES.IF COOLING FAN DONT WORK REPLACE THE MOTOR.IF FAN WORKS.COOLANT TEMPERATURE SENSOR IS BAD.ALSO HAVE CAR SCANNED TO SEE WHAT CAUSING CHECK ENGINE LIGHT TO COME ON.

you might want to check the fan relay switch it out with one that you dont need tho run the car then if the car stays cool you know that its the relay. but if that doesnt solve your problem try replaceing the temp sending unit that controls the fan there should be to temp sending unit one for the guage and oe for the fan.help this help.

 buy manual, see if fan runs with alt power source(jumper wires), check temp sending unit 

Don't risk a fire-Put in your own relay, and run a min of 12 gage wire from the battery with a inline fuse. On the other on/off terminals, run a switch and find any 12v source that is turned on by the key. You can use a relay for lighting, found at any autozone for around $5.