We haven't had this '87 Z28 with a 305 & carb for very long. Unless the A/C is on, the radiator fan doesn't kick in 90% of the time. The little original Camero book said the radiator fan will start after turning the engine is off if the temp is still hot. Anyway, a radiator shop changed a sensor switch & we thought it was okay but then back to 240 degrees real quick. So, changed the engine temperature sensor. Yesterday the fan worked w/out the A/C on but only if the ignition key was "on" without the engine running. Today, back to radiator fan only working when A/C is on. Does anyone have any ideas about this?

 

is it the duel electic fan? im not sure on camaros. anyway, my car has the duel fans and they dont turn on either, from what im told the easiest way to fix this is to just wire them to a switch and turn the switch on when you want the fans on. i dont remember how to do it though.

 

If your fans only works with the AC is on but not when the engine is hot, then you need a new fan switch... It's just a little sensor locatied on the right head at the rear.. look between #6 and #8 plugs and down a little.... How it works is, when the sensor gets hot the sensor grounds the fans to the engine, then the fans come on. When the engine cools down the sensor stops grounding the fans. It's cost less the $10... Goodluck!

 

hmm maybe thats what mine is too...im gonna go check that out...

 

Hey, thanks! We'll try it tomorrow. If that's not the answer do you think it'd be worth the investment in an electrcal engine diagnostic to identify the problem(s) with the radiator fan?

 

I have a 91 z-28 and my fans do the same thing. Please let us know it that works.

 

Yes guys, that would be the problem if the fans only work with the AC....

 

1988 IROCZ with dual fans:
There's a primary fan, and a heavy duty fan, each has it's own independant control circuit.

The primary fan is turn on by a fan relay controlled by the ECM to a specific temperature using temperature data from the CTS, and is over-ridden by the A/C high pressure switch when it closes it turns on the fan relay, and signals a digital input to the ECM, the ECM uses it to determine how to handle the extra load .i.e. add more fuel.
The solid state switch in the ECM can fail to turn the relay on, or off. Unfortunately the ECM has to be replaced to repair this failure. This circuit only controls the fan's relay, not the fan itself.

The Heavy duty fan relay is controlled by a heavy duty fan switch in the passenger side cylinder head.

Either switch can fail open, or closed.
Test either fan by applying 12v to either fan's relay "A" terminal. If the fan's turn on, then test the fan's relay with the ignition on and grounding the relay's "F" terminal; drk grn/wht wire. If the fans turn on, the wiring, relays, and fans are OK.

The only other time the primary fan turns on is by DTC mode.

 

Could be a short or bad connection,or bad fan motor(if you have duel fans)

 

I'm sure that he has a single. He has a carb car and they didn't come with dual fans. That was on TPI models..


Dude just change the Fan switch like I aready posted..