92 RS camaro with the 305. Car is bone stock, but it's getting to hot. I have replaced the radiator, thermostat (195f), flushed the system, fresh coolant, new water temp sensor on manifold next to thermostat housing, new radiator cap, and I ran a pressure test. Car is holding pressure no problem, water pump is also operating good.

The only thing I've noticed that does not seem to work right is the fan. I know it works, I did the 9V battery test. And I have witnessed the fan kicking on before. But when it was running hot earlier it was not kicking on at all. Also the heater core is fineas well. What else am I mssing?

 

turn on your A/C and the radiator fan will kick on.

 

I'll check that out, but I do have an update. The fan finally kicked on but it is not kicking on until the temp gauge is reading in the red. The car is not showing any signs of over heating at all though. The fan kicks on, the temp gauge goes down, the fan shuts off. But I feel the fan is kicking on to late, also the car seems to heat up faster when it is moving, and when the car is not moving the temp goes down a little bit. I am actually very confused by all of this... Is the switch that turns the fan on and off bad? Why would the car be heating up and not cooling down when I'm moving?

 

These temp gauges on a good day are far from accurate. If the car is not boiling over into the overflow tank, then it's not overheating. Normal operating temp for a 305 TBI car is 220.

I'd try replacing the temp sender for the gauge - it's in driver side head, between #1 & #3 spark plugs. Has a single dark green wire to it.

 

i believe i read somewhere the fan in a 92 tbi car doesnt come on till 238*.

 

Is your air dam intact or even there? Makes airflow through the radiator possible while the car is moving. Look under the front of the car for a black plastic panel about 6-8 inches tall sticking down from the radiator base area. If not there you can also do a search for air dam on this cooling forum for pictures of it. You need one

 

Wow, thanks for all the responses. It makes sense if it's true that the fan is not kicking on till 238f. Because that's about when it is coming on. I will also replace the sending unit asap, but the car is not boiling over at all. So maybe I'm just jumping the gun? Also I did an oil change today at work on tue car. There is no black air damn under the front bumper. Just a big opening, so I'm guessing I need to find one. Where can I find one at online? Right now I'm just running around with the AC turned on so the fan stays on. The temp gauge is staying right below the 220f mark. Thanks again for all the help.

 

http://thirdgenranch.com/-strse-958/...air/Detail.bok

 

Thanks, I'll get that ordered asap. Also I'm reading that some models of Camaro came with dual fans? I have a single electric fan that somebody spliced into some wires in a loom under the hood.

 

rs models with a v6 and a 305 tbi came with a single fan

 

234° F actually. If you want the fan to come up at the same time, or shortly after the thermostat opens, just get a radiator mounted aftermarket temperature feeler to operate the fan. Set it to 200° F and you should be good.

 

I think my next step is to replace my air dam, because it is in fact non existent on my car at this moment. If I'm still having issues after that, then I will install a new fan switch sensor to start the fan sooner. After that then I'm sure it will boil down to a faulty gauge since I'm having issues with a few of the gauges on my cluster. But as we speak the car is not over heating because I'm keeping my AC in the on position as I drive around. It keeps it below 220F, so that will do fine until I get the air dam ordered and installed. Thank you everybody for your help, this has been on of the best forums I've ever been apart of so far.

 

Now understand, the air dam will only help at speeds above 35mph (ie NOT stop & go traffic) - your fans at these higher speeds do no good at all (with the air dam in place that is). And it mounts directly under the radiator.

Some are confused as to how it works. Alot of folks think it 'catches' air and redirects it into the radiator, but it doesn't. It creates a low pressure area behind the radiator. This creates a vacuum if you will, and makes air rush to the low pressure area (vacuum) ... it rushes in from in front of the radiator, thus the air rushes through the radiator. So the air dam creates a vacuum that sucks in air through the radiator, rather than directing air through the radiator.

So, get that air dam replaced, try another fan switch (because it's quite possible that a previous owner replaced the fan switch with the wrong one), and you could also try a 180* thermostat (but no lower than 180).

 

Thanks for explaining to me how that works, because I really thought it pulled air into that area. Still though most of my driving in town is 40+ MPH, and I typically do anywhere from 5-10MPH over the posted speed limit. Maybe I will try to keep it under 40MPH to see how that works. But I will still install one, then install a different fan switch. Once again thanks for all the info!

 

i actually just ordered an air dam from my local gm dealer and it only cost me $47

 

I was able to borrow a contactless thermometer from a mechanic at work, drove the car until it was at 220* and took the temp off the thermostat housing. While the temp gauge read 220*+ the thermostat housing was only at 200*. So I now know my temp gauge is about 20* off from the actual temp. But still I'm ordering an air dam, replacing the fan switch, and possibly dropping in a 180* thermostat.

 

I use a 180* thermostat and really like how the car runs and stays cool with it. Also, I have a fan switch that turns the fan on at 195*, however when the fan kicks on, my gauge reads a tad over 220*.

 

TPI parts sells a low temp fan switch that turns the fan on at 200 degrees and off at 185.
They work very well and really keep the temp down.

The air dam is important when the car is moving and most firebirds seem to be missing them.

I saw another thread where a member had posted links to a site that also sold air dams and there were three different styles.

Try a low temp fan switch,you'll be amazed at the difference.
You'll have to go underneath the car to change it out though and it isn't much fun.

The original fan switch has a blue collar and is marked 106c (celcius) and doesn't turn the fan on until over 220.

The low temp switch from TPI parts costs about $36

 

Do you have the part number for the fan switch?

 

Jim,

I would appreciate that part number too, running 190 when it's cool like this is great but summer is coming!

 

Here is a link to the TPI site where the switch is.

They are $32 plus shipping.

http://tpiparts.net/inc/sdetail/293

They are a family owned business that specializes in Firebird and Camaro performance.

I had bought mine direct for their website and it showed up in two days!

So far it works great,the gauge never goes near the middle anymore,it always stays at or lower than the first quarter mark,and I'm still running the stock thermostat.

 

i have a 92 camaro rs that i put a 350 in, my stock 305 overheated all the time, i put a 350 in with an edelbrock carb, replaced radiator, rad cap, thermostat, waterpump, upper and lower rad hoses, fan is on at all times, took the air dam out to get more air flow. im completly out of ideas here, its a brand new motor.
any ideas?? need help asap.

 

you MAY have a malfunctioning temp gauge.try running a aftermarket temp gauge for a test. if your original dash temp gauge is shot you can have it repaired .good luck!

 

There is your problem there, or at least 80% of it. You have to have the air dam or the car will over heat on the highway. You must have it to keep a good functioning cooling system.

How hot is hot? These cars were built to run at 195-225 degrees. Unless your coolant is boiling out of your overflow, you should be fine. My stock gauge reads 20* high, verified with an infared thermometer.

 

mine reads 220- 240 on the gauge but the water outlet to the radiator reads 190 with a digital thermometer. i did change my old sending unit out in the head because the temp never read over 180. i am starting to wonder if these new sending units are calibrated correctly for our cars. the new sending unit reads 40 to 50 degrees hotter than the original. any ideas on that?

 

any my car never boils over either. i think our problem lies in the sending unit all parts being as they should be in the cooling system.

 

well i took the air dam out and now it stays cooler for a longer period..i looked at where it was and the air was being restricted. now it gets all the air it can. im pretty sure the guage is reading right aswell b/c it stays down for about 15-20 minutes then goes to about 220 for 10 minutes and shoots up from there.

 

i had problems with my car overheating and it was because my fan was not kicking on, had it wired to run when the cars on, should i still put my airdam back on, it has been off for a few monthes, its not overheating staying at 220

 

if its staying cool without the air dam then theres no need for it. i personaly think the air dam restricts airflow to the radiator.

 

Thanks

 

I'd prefer a cooling system that works without E-fan over one where the fan is on all the time.

E-fans fail after having reached the end of their lifespan which is listed in operating hours.

They are not intended to run from the moment the car is switched on untill it's switched off.

If you want a fan thats permanently on, consider a mechanical clutch driven fan. Some of the first thirdgens still had them untill they were replaced by the superior E-fan setup.

I can drive for 2 hours without using the fan. Reason for that is having a working cooling system, the way it's intended to work on thirdgens. The airdam is one of the major components in this setup. Searching through this subforum will bring up several explanations on how it works, and Camaronewbie took the time to repeat it all in this post.

@nobrakes, if your thirdgen runs cooler without airdam thats fine. It's not generally the case for other thirdgen owners however since these cars did not lug around that $50 piece of plastic without reason.

 

Wow, I am experiencing the same problem. Car don't run under 220 but I got gas left key on praying fan would come on and it did once it got in the red. I just bought the car but when the guy trailered it to my house, when he first started it the fan was on ?? When the car was cold? So I'm not sure if the fan switch went bad now or what??

 

it doesn't, if it did, they wouldn't have put it on there. In fact,for Firebirds, without it our cars overheat almost instantly.

 

If it's not boiling out of the overflow, it's not "overheating".

Replace the fan switch on the passenger side, flush and fill the radiator. Ensure the airdam is in tact and correctly attached.

If the car isn't boiling over, mostlikely your gauge is off. Get an IR temp gauge and measure the temp at the thermostat housing when the is "hot". this will give you a good idea what your temp actually is regardless of what the gauge reads in the car.

 

What position was your heater switch in when the car started cold? Mine typically runs at 220 - 230 on the guage but doesn't boil over so I don't worry about it. the last time it boiled over was on a hot summer day and my single fan motor had died.

 

I also want to mention that with the HVAC control in the AC position your fan, at least one of them should come on.

 

Just install this adjustable thermostat set at around 190* and a 180* coolant thermostat and you will be amazed at how it helps keep it at a lower temperature.IMO the stock system runs way to high at 225*. My engine preforms better at around. 190* Seriously,install this switch ,it does not have all the extra stuff of the more complicated sets but you don't need that. This is just a basic fan switch and its easy and cheap to do.If you don't like it your only out the $17.99 you spent on it.= http://www.autozone.com/autozone/par...ier=267187_0_0_

 

Ok i had been wondering about this, mines a 89 rs with 305 tbi and i had overheating issues till i realized my radiator cap was bad, fan kicks on for me at about 220 on the gauge if thats normal then i guess the car is running fine but if i run it too long like that the coolant starts to boil a bit and i get an odd smell in the cab (im assuming coolant vapors). It's been hot here the past few days so im wondering if these engines just dont like the heat or something. i did do a bypass of my heater core so coolant just goes right from the engine back to the outlet side of the radiator (where the return line from heater core goes).

I'd like to think that wouldn't be a big issue though as it only changes me not being able to use heater core as secondary cooler. (blower fan not currently working due to bad relay).

 

I would be pulling my hair out if the car got into and over 200* all the time.

I would use the 180* thermostat and set the controller to 190*

If you have a single fan controlled by a switch in the head here’s a solution to your overheating problem.

Don't destroy the connector going to the switch in the head just cut it back a few inches so you can put it back on at a later date if you want.

You can add wire to the ground wire that the switch is connected to so you can mount it where you want.

If you decide to do this then let me know and I will tell you an easy way to set the adjustable switch to the temp you want.

You can install a second fan on a totally independent (totally separate) circuit as back up if you want. I also have a simple diagram for that.

Ignore the diagram that comes with the switch.
The switch is Part # 733653

http://www.autozone.com/autozone/par...96537&cmpid=cj

 

Okay do you have a manual switch for the radiator fan motor? I had a Corvette shop look at my 92 RS 305 Auto and they said this is the best way to prevent any damage and a for sure way to keep this issue away. Take some DC THW wire from any auto shop store and then wire it up to the positive side with a splitter or forks. Key notes to remember (Always Turn it on before it gets to 200 degrees) and have the switch off when you fire it up. Drains volts\amps when you have too much going on during take off.