I have a 1988 camaro rs with the 305 TBI, and i cannot get the fan to come on when the car gets hot. It will come on when i turn the AC on so i know that the fan is still good. I have put a new fan relay in it, and changed the temp sensor on the intake manifold next to the thermostat. I have read on these forums to try and figure out where another temp sensor might be, but I'm not sure since it isnt a TPI car. i did try to test one that is on the head above the starter but im not sure i did it right. Any help would be appreciated.

 

Ok im going through the same problems so ill tell what i have learned on here so far. You tested the right one, the fan switch is in the head above the starter, if you havent changed that do it since they arent that much and the cool thing is you can go to advance auto and find the oe replacement then get in their gp sorensen book and there are pics of other sensors that have the same threads and size as the oe replacement but at cooler temp settings so the fan will come on sooner. Next take a look at the wire that plugs into the switch, if its not burnt or the pigtail is not brittle from heat and years of use that should be ok. From what i have read you can get a piece of wire, (turn on your ignition to make this work,) and take that wire and strip both ends stick one end in the pigtail and ground the other end this should kick the fan on showing that the realy is good if it does not the realy may be bad or the fan switch wire is bad somewhere. Is your temp gauge working? If it is then your temp sensor is good. Oh and you said that it comes on with the ac from what ive also read if the fan does come on then the realy should be good. I hope this makes sense and helps if you need any more info ill try to help. But search the forums i had to do alot of reading to get what little bit of knowledge ive gotten about this so far.

 

From what i have read you can get a piece of wire, (turn on your ignition to make this work,) and take that wire and strip both ends stick one end in the pigtail and ground the other end this should kick the fan on showing that the realy is good if it does not the realy may be bad or the fan switch wire is bad somewhere.

I tried this and i got nothing and since i replaced the relay im starting to think that i have a broken wire somewhere. I am still going to buy a new switch and the pigtail and replace both. My temp gauge works, and i think that it is controlled by a separate sensor on the head behind the alternator. I was messing with that wire and it was making my temp gauge jump around so that has nothing to do with it on my car. Thanks for the help i will keep reading.

 

not a problem ive got a gremlin running loose in mine i replaced part of my wire that was burnt hooked everything up today and my car went past 220 ideling and the fan never came on so im gonna replace my switch and see what happens next

 

88camarojake6, I assume your car has dual fans? As green92 says, the fan switch is on the passenger side head between #6 & #8 cylinder. There should be a wire attached to it. Remove the wire where it is attached and ground it, the ignition switch should be in the run position. If the fan works, the switch is bad so you can replace it. A lot of the time this wire is missing or burnt off. If you need a new switch, this is the time to get one that will turn on the fan sooner. You should replace the thermostat if you get a fan switch that comes on sooner. If you are going to go that route, reply about what you are doing and what you have found and I will check in tomorrow or someone with more knowledge than I may reply also.

 

Painless Wiring also makes a nice kit that includes the fan switch, relay, and all wiring you need. The one I got kicks on at 185* and off at 170* Fan switch is a direct replacement for the stock one. 20 minute install ... well ... hour if you include cleaning up all the anti-freeze. "Oh yea, there's coolant in there ... "

 

I looked on the advance auto website the part number for the pigtail is ps35161 alt # ls770

also the fan switch (oe temp) is ts85
hope this helps the pigtail is 8.29 the switch is 26.99

 

305 TBI, probably single fan.
If so, the relay is turned on by EITHER the control switch, shown
above, OR the AC on, setting a high-side pressure switch. If the
fan comes on in this instance, fan & relay are operational.

However, from personal experience...
If the fan is degrading, it will run, but not as well, and draw
excessive current, causing a relay burnout failure. Symptom
is obvious -- overheating/charring/deformation of the relay
connector. Check for that also.

Good luck,
kk

 

Thanks For the help guys, i think ive got it figured out now, but my starter just went out. Thanks For the help!!!

 

Alright, So I got my starter working. I let the car idle until it started getting hot, and the fan didn't come on. I have replaced the temperature switch twice now, replaced the pigtail, and the relay. When i ground the wire the fan does come on. What else could be wrong. I have replaced about everything there is to replace. I'm all out of ideas, if anyone has a suggestion i would be happy to hear it. Thanks!!!

 

88camaro, are you using any type of sealant on the fan switch threads? If you are, that may be your problem, sealant won`t allow the switch to ground properly.

 

I've used a pipe thread compound, but it needs to have something doesn't it or it might leak? What do other people do about this problem?

 

I`ve talked to some that just tighten the switch and it does not leak, I never have that kind of luck. It sounds "hokey" but the last switch I replaced that leaked, I removed it and used some sealer then reinstalled it and attached a small hose clamp around the sender with a ground wire attached to it and it worked just fine. I think some people just tighten them until they stop leaking, I don`t like doing that to a fitting I will need to replace some day, it makes it too hard to remove.