in my 10 years of workin on cars and trucks ive never seen something this messd up. the fans on my 95 z28 havent workd since i bought it im rebuilding it to make it road worthy i checkd the relays bridged em no go on anything i was about to just hookem up to switchs ang go i got curious and want to see if the mass air flow senser was goo i pulled it and the fans came to life both no ac runin and a cold start not even warmin up but they came on i pluged the sensor back in they died. wtf? new relays and still only work if i start it and disconect the maf sensor anybody got any ideas its not a short not a groud problem i wired up new ground wires checked the wires . i really dont want to spend a whole weekend re wiring everything for no reason. any ideas?

 

The PCM will turn on the fans to protect the engine depending on the trouble code (DTC) it sees. When you ran with the MAF disconnected it generated a DTC that among other things forced the fans ON. By doing that you proved the circuitry from the PCM to the fans is good.

You should look at the ECT (Engine Coolant Temp) sensor at the water pump, not to be confused with the temp gage sender.
Disconnect the sensor plug and measure voltage between the Black (PCM ground) and Yellow PCM (signal) wires. With the key ON you should see 5 Volts. If not the wiring from connector to PCM is bad, or there is a problem with the C (clear) or the B (black) connectors on the PCM, a bad ground on the PCM, or even a bad PCM.

With a jumper short the Yellow & Black leads on the ECT connector to each other. This simulates a very hot engine and force the fans on. If the fans come on it indicates the sensor is bad, if the fans do not come on, the wiring or PCM could be bad.