Ok so i wanted to avoid posting another cooling question but unfortunately my problem wasnt that easy. So here it goes, i have a 92 3.1L V6 that over heats only when the car is stopped/idle, once i get going im fine, also here are the parts that i have replaced...

-radiator flushed
-thermostat w/gasket and gasket seal
-temperature sensor (on the block)
-fan relay
-fan motor

some things to keep in mind is i havent yet got coolant in the a/c lines, but this couldn't be it because before it started to over heat, the fan did come on, also when i test the relay housing itself, the fan does come on at both speeds. I need help on this one because im swamped, im seriously thinking to just install a by pass switch, but i dont want to do that being that i just want the thing to run like normal.

 

also forgot to add that the water pump is working, the coolant is circulating in the radiator.

 

when you say the fan comes on, does it come on when the AC is off? Does it stay on?

 

the fan doesnt come on thats the problem, if i run a wire in the relay housing then it comes on, i originally thought that the fan motor might have been going out and i heard that the fan clutch might be shot so i put in a new motor, but to no avail, still wont turn on.

 

Has to be a bad connection,bad relay socket etc.-
get the car up to the temp that the fan is supposed to
come on at,then wiggle the connections that have to
do with the fan circuit,wiggle and partly pull up the fan
relay-if fan starts or "kicks" you have found the problem
if the relay socket is the problem might be able to solve
the trouble by using a needle nose pliers to slightly
twist the pins of the relay to make a better connection.
Also make sure no thread tape is on the fan thermostat
as that has to ground to the head to activate the fan.

 

I already had to do that to the socket on the relay to get it to fit in and checked the wiring on the fan, its ok. So I'm going to have a fiend of mine thats in mechanic school take a look at the wiring diagram to see what we can figure out, will keep posted with the result later this week, was thinking maybe it is a bad fan switch, will let our result of this test be posted to narrow down more the search...

 

So i got it down to a bad fan switch, but the problem is that i dont know where its located, my friend will let me know the results later this week, where its located. but if anyone can please let me know where its located, or what it looks like, will be of a great help to me, being the sooner i fix this the better, that way i can move on to my other problems. I have the 3.1 L V6 engine.

 

lol just found out 92s dont have coolant fan switches because the ecm controls the fan. so now im thinking its no the wiring, because when i jump the relay housing, it turns on the fan. so that tells me that the fan is good, and the wiring is good, so now im having a friend look at it by putting in an aftermarket chip and telling it that the fan has to come on at 195 degs. instead of the factory set 220 degs. for added safety from overheating, but ill keep posted on the result

 

Even if it is controlled by the ECU, couldn't it still have the "switch"? ?
I'm not really sure, that's why I'm asking. What the switch does is it sits in the a coolant passage and measures temperature, so it could still be that (at least that's what i was led to believe when i replaced mine). are you sure factor is 220? that's usually maxed out.

 

it does have a temperature sensing switch (which i have changed), but on other models theres also a coolant fan switch i believe its from 90-92 ecms dont have this type of fan switch. sorry forgot to specify.

 

ah probably v6 specific. I just figured it could be similar between that and my 92 RS TBI