OK, I have a weird problem with one of the coolant fans. It doesnt come on when the temp rises and the car overheats if your not driving at a good speed. If you turn on the A/C it cools off just fine. I have already removed the fan and tested it with 12V and its works just fine. I was wondering about changing the temp sensor in the driver side head but the guage works fine so I figured I would ask to see if anyone else has that problem also or has been accross that before. I have a 90 RS camaro also with the same problem and changed the sensor with no difference so I just make sure that the defrost or AC is on when in traffic. Its a pain but it works OK. Seems like camaros are famous for this condition. Any input on this problem would be appreciated.

 

The fan settings from stock are stupid hot.
Question is whether that's all there is to it.
If you can get them programmed down to
more sensible temps then that would make
it more clear, if something was actually wrong
other than bad engineering judgement.

The overheating could be radiator cap not
holding pressure, against the operating temp.
On these cars the fans don't kick until above
boiling, you need tight pressure seal to suppress
it. Otherwise you'll make steam in the heads
and then it's a runaway train.

 

yeah, but he says that one fan comes on and the other one doesn't unless the A/C is on.... Sounds strange to me. I'm going to check mine. I thought they always came on together but I haven't paid that close attention. I also overheat in traffic unless A/C is running. Maybe because ony one fan is running????? I'm going to check.......

 

I checked the radiator cap and all of the fuses, etc. and everything seems to be good to go. I am just confused about it. Like I stated earlier that I actually tested the fan itself and if works. It always worked fine and then one day I noticed it heating up to 220F and I started probing around to see what was up. I have owned many camaros in the past (mostly late 80's and early 90's and I have had that problem with many of them and my 90 still has the problem and cant figure it out. Everything checks out OK. I heard along time ago that that circuit in the computer burns out or somehow misfunctions but I was hoping that nothing is that serious in the 4th generations. Anyone else out there have any problems?

 

Well, I went out during lunch yesterday and was going to check out the fan situation but I just plain forgot as I was kinda in a hurry to get back to work. I'll be going out again today at lunch and I'll put a post it on the dash to remind me. This has also bothered me for about 3 years and I haven't had the time to really nail the problem. I did the basics... flush & replace the coolant, bled air out of system, new water pump (old one went bad), pressure tested the radiator cap, & new thermostat. I can't remember what temperature thermostat I bought but I think that it was 160°. I have a theory on this but I haven't had time to test it. If you put in a 160° stat as opposed to a 180°, your coolant has less time to cool in the radiator causing you to run hotter. I run about 230° when sitting in traffic. If I run the A/C, I can cool it off to 210°. I'm not sure if the car has always done this and I wasn't paying close attention but I know I'm not comfortable with it now. A lot of guys on this website have the same problem but I haven't seen any definite solution other than the basics and making sure that you have bled the system of all of its air. Even after they do this stuff, I don't know what they typically run at. Who knows...., maybe I have a little air in my system and I don't even know... Now my car is completely stock all the way down to the air filter. I figure that with all oem parts, I should be able to sit in traffic below 210° without having to force the fans on. Some guys put in a manual switch to the electric fans instead of running the A/C. I can only imagine that if you do this and forget to turn the switch off at speed, you'll burn the motors up. This winter, I plan on going over the cooling system. I'll flush and replace the fluid and put in a NEW 180° stat and make sure there is NO air in the system and we'll see what happens.
For now I'll see how my fans work, maybe were on to something there....

 

I was just out at lunch checking out my situation. Both of my fans come on without the A/C running when I hit ~230°. They are supposed to come on at 210° so either my gauge is not right or the temperature sensor is not right. Once they're on, it'll cool me off to about 215° (according to the gauge). Just so you know, it seems that both fans should come on without A/C running, not just one...

 

OK jkichline, one thing that I havent done is bleed the air out of my system. I saw in another thread you put in a link about that and I clicked on it and it wasnt a valid thread. What is the procedur? I really dont think that is my problem but I dont want to leave any stones unturned. When I checked by fan manually, I did remove the radiator and all the other stuff and just did a good cleaning of all the parts. But the problem started before I removed everything and I still dont think that is my problem. I will let the car run for awhile and let it get hot until I think its dangerous to see if the fans come on at all. They dont up to 220F I know but if yours are coming on at 230F, maybe I am just not waiting long enough. With an aluminum engine and heads, I get nervous about letting it get hot. I know that it never used to get that hot and something has definetly changed. I may try another sensor also since it has a 3 prong plug and may drive the guage and fan seperatly and maybe that will help find something. Its so hard to see the fans come on because they are so quiet and at a bad angle to actually see anything but I will give it a go and see what happens.