I have a 91 z28 305tpi and my electric fans behind the radiator do not work. I know one is suppose to kick in once the car is warmed up i think driver side but none of them work at all. How do i fix this is it a sensor, a wire or needs to be replaced?

 

Could be a number of things. Fan motors have died. Relays gone bad. Wiring is damaged. Fan sensor/ switch is bad.

With the ignition on turn on the A/C. Does the fan kick on? If the fan comes on when you turn on the A/C the problem IMO is probably a bad sensor/ switch. Not sure if the Dual fans on a Z28 are controlled by the ECU via a sensor input or if you have a switch like single fan guys have.

If the fans don't come on when you start the A/C then the problem is with a relay or the fans themselves I think. I'm sure someone will chime in with more info.