Castro

I love my cars to death but man GM so screwed up the camaro's with the excess heat because of emissions laws...anyway enough venting.

Ok I know this is tried and tried topic. I actually went out and got a GM service manual for the 92 off ebay.

My car has 2 fans. The primary and the secondary. After looking at the book the primary fan is on the right side of the radiator (opposite side of the battery)

Ok so today I get home and my car went all the way up to 260 before the primary fan came on. As soon as the fan came on boom the temp dropped down to 220. My question is why isn't the primary kicking on faster and what about the secondary.

At first I thought my primary wasn't kicking on but the book shows in the diagram that fan is the primary.

Its crazy I don't know if I can even fix this I am looking at the trouble shooting steps in the book and its just like going right over my head.

So any thoughts on what could be causing the fans not to kick on at lower temps? Anything I should be looking for? THe car has a little over 100k right now and from as early as I have owned I know the temp has gone up high...

I am affraid to take it to a mechanic and have them just do the most expensive thing you know...

aklim

The fan should be on when the ECM sees a certain temperature. I would use a scantool to see what temp the ECM sees when it comes on and compare it to the guage. The guage is not the most accurate thing in the world.

Castro

Small typo I was a little tired last nite...the primary fan kicks on at 240 maybe 239...right before it hits that yellow line which I say is 240 because the line to the left is 220 and to the right is 260 hence 240.

The other fan is just not kicking on...grrrr....I came today to work with the ac on eventhough it has wasn't cooling to see if I could drive up the PSI presure because according to the book when it hits a certain PSI the fan kicks on...

Castro

aklim,

thanks for the response. Is this scan tool cheap? Is it rentable?

I think today I might order the fan switches as recommended over thirdgen.org

Rice Killer87

a scan tool is not cheap,and im not sure if tis rentable or not.

the secondary fan should come on when u turn the A/C on reguardless...not about some PSI crap (from what i know). if u keep running the A/C and it doesnt have any freon in it,it could burn up the compressor...so be careful.

try running the car untill it gets to about 240 like u said,and pop the hood and put ur hand on the valve covers. if its really at 240 or so,it should start burning your hand pretty quick.

hope that helps

Zepher

At least one of your fans comes on, neither one of mine would come on so I wired each relay to a swtich so I could control them individually.
I'm too lazy to find the problem and fix it so I just run the primary one on all the time.

Damon

Make sure both fans actually WORK before you start going through the electrical system/ECM.

If you aren't getting any fans until ~240 then it sounds like you're only getting fan operation from what I call the "switch of last resort." That's the temp switch in the passenger side head between cylinders 6 & 8. It's designed to be a "fail safe" if for some reason the ECM doesn't turn on the fans. It does it for you mechanically by activating the SAME relay that the ECM would (by grounding the appropriate terminal on the relay, just like the ECM is supposed to).

What I DON'T remember is if this "switch of last resort" is designed to activate BOTH fans, or just one. I think it's both, but don't quote me on that.

Wish I could help more, but my memory is way too foggy beyond this point.

I would replace the CTS (Coolant temp sensor) on the engine just for good measure. It's the sensor that the ECM relies on to tell it what temp the coolant is. It's a 2-wire up on the intake near the thermostat. If the ECM doesn't get an accurate reading from this sensor it will never turn on the fans, obviously.

BTW- the ECM (with a stock chip in it) should turn on the fans at 228*F as read from the CTS sensor by the ECM. That's with the A/C OFF.

aklim

The ECM one seems to work or so I have been led to believe by your reply. If not, please let me know. The other one you can easily test. You know where your switch is? It should be somewhere on the head between cylinders 6 & 8. take that plug out and short it to the ground. If that doesn't make the fan come on, you have a bad fan or relay. If it does, you might have a bad switch.

onefastgta

Instead of buying the aftermarket temp switches, I'd just leave the stock thermostat in it, or put in a 180, and run the secondary fan all the time by grounding the wire.

Castro

Well this weekend I went to autozone and got the 2 sensors...the one that goes in front of the engine (which i installed) and the one that goes on the side...still haven't installed that one. (PS sensors were 10 bucks each)

Temp still goes up to 239-240 but I noticed that both fans come on now. Interesting huh?

So this week I will change the side one and see what happens...both my fans are fully functioning though...

Ray86IROC

I'd skip the lower temp fan switch junk and just wire the fans up with a new relay/fuse setup and a manual switch. Keep em on most all the time that way and eliminate any wiring gremlins that may be causing them to work intermittently.... You can get all the wiring, a 30 amp relay, switch, fuse block etc for about the price of a lower temp fan switch most likely... I mounted a little rocker switch in mine underneath where the cigarette lighter is to control 'em... I prefer having control over them myself...

Drkhrse89

I know that I am chiming in late here but the primary fan will not come on until 228* (yes I know that is really late) and the secondary fan will turn on with the AC or if it reaches 240+*. Replacing the CTS was a great thing, but replacing the secondary fan switch is really not going to do that much good. The best way to lower it is, like aklim said, go into the ECM and change when the fan turns on. I had chased a overheating problem for a good year before one of my friends helped me with the prom and now I have no troubles. The fan kicks on at ~170* and off at ~160*. The switch is a great idea but it can easily be forgotten and then you are left with a dead battery. Those are my thoughts on it.

Castro

I know they have a good article over at thirdgen.org about wiring in 2 switches one for the primary and one for the secondary. The thing is that the article doesn't show the wiring detail. I need to get a hold of some detailed instructions.

But still its strange that my primary is kicking on at 239-240...The only other thing that someone mentioned on here was that the interior guage might be showing the wrong temp which i don't think it is just because its like clock work when it hits 239-240...

I would love to wire in the switches though! Anyone have any pics or diagrams or know where to locate them on the web?

PS great feedback!!

Drkhrse89

I hooked mine up to a laptop to see if it was reading right and it was about 10* off. The best thing would be to get an aftermarket water temp guage to see if it is right. If you are gunho about wiring up some switches I say go for it. Look around the net for wiring diagrams, it is pretty much the same way to wire fan switches as it is to wire a house switch.

cralarcon_IROCZ

Are the aftermarket switches that are offered the switch that sends the signal to the ecm...or is it the switch that is located on the cyclinder head???