my rad fans dont work unless the a/c is on. is the fan relay shot or is there a temp. sensor that isnt working? because without the a/c makin the fans run im gonna overheat.

do you have a water temp gauge?



stock ecu?



fan mod?

No.



Yes.



and no.

do the fan mod. Look it up here or on the other forum.

The fan mod is good, but it doesn't address WHY you fans aren't coming on as they should. The prime suspects would be the thermoswitch or at least one of the fan relays. Since the fans come on with AC, I'd start with changing the stock thermoswitch first, and while I was at it, I'd swap to the FC (89-91) thermoswitch. IIRC, ~$40. It SHOULD turn you fans on sooner, 210 deg. F. instead of 225 deg. F.

If they still don't work, start checking relays.

I'd take the time to check the fan relays. If they are corroded or wet in any way then they will not operate properly.

that could be it, because it rains a lot here.