i have an 86 trans am , i dropped a built 355 tpi in there, with a aluminum 3 row rad, the ecm and wiring is from a 87 iroc, i deleted the a/c, even the heater, only gonna drive in summer when weather is good. now my question,, i dont have dual fans in the car i have the stock 86 single fan, since i dont have a/c , and i deleted half the harness to have only one relay to my fan,,,, now what should i use to trigger that single fan? i have, 1. the stock temp switch on pass head,2.a temp switch on my new rad 3. the ecm that takes the info from that temp switch on the intake below throttle body, can i use the gre/wh wire from the ecm and both switches on the same relay?? should i rely only on ecm? only on 1 switch? 2 switches? if i use the ecm at all,,,, since i have an 87 wiring, do i ground, or open the blue wire from the a/c? cause i dont have a/c ,,,the car i took the ecm and wire from used to have a/c. if i dont use the ecm,, can i just leave it like that or is there something i should change not to mess up anything,,,,,, i just dont wanna try a bunch of things, want to wire the car properly once,, and hide harness with loom once and for all,thanks.sorry for the looooong question

 

If you dropped a 355 in it you need to tune it anyway, so if your going to modify the calibration use the ECM's fan output control to run the fan at your desired on/off temps.

You can use the $6E (1989) mask with that ECM which will delete the cold start injector.

You should be able to tell the ECM if the AC pressure switch is normally open or normally closed, so you can do either.

-- Joe

 

thank you very much!ill use the passenger side temp switch too as a back up at higher temp,its only a ground, shouldnt matter right?i see that the 2.8 was set up like that in my 86 shop manual.

 

Yep, there is nothing wrong with using it as a back up fail safe. It will ground at ~240 depending on which part number you use.

The TBI cars were run primarily off the fan switch as their ECM didn't have fan control.

-- Joe

 

I have an 86 TPI 305 camaro. It has a single cooling fan. The problem I am having is that I can't figure out where the cooling fan relay is supposed to be mounted. On my car there is one on the right side of the radiator support next to the battery but I don't know if this is where it is supposed to be or if someone just put it there since it is an aftermarket relay. On some cars ie: 87 and later I typically see a distribution block there. Also I cannot find where the unswitched power connection is to the relay. Someone tapped into the large fusible link near the battery on my car. I would think there should be a connector for this. The fusible link has 4 wires coming out of it and appears to be part of the battery lead. One of the wires is cut ie: the small red or orange wire coming out of this link. if someone can help me to figure this out that would be great.