92 bird cooling fan not coming on(relay replaced)

[tk6500]

can some one shed some light on this? I have replaced the fan also. The fan comes on when the a/c is on but not when the temp is up?

[87bluebird]

Is this your second fan you're talking about? If so, there may be a temp sensor that likely is "in the loop," too. My '89 had the same problem with the second fan and the problem was a heat sensor that's in the passenger side head. The thing fell apart in my hand when I went to look at it - of course the heads get as hot as anything in the engine, yeah? I haven't yet replaced it since I don't drive the car but occasionally at SCCA races. Instead, I put a switch on it to make that fan always on - when the car heats up, I turn the switch on to make the fan run.