Hello,

New to these sites so please bare with me.

I have a 96 Camaro Z28. It runs well but overheats when stuck at traffic lights and cools down once car is able to move.

I haven't notice/heard my fan kicking on. I understand from previous threads that I should check my fan directly, So how do I do that?

As far as changing my thermostat or fan temperature sensor, where are they located?

Thanks

 

How high does the temp get at stoplights? Does it run cooler the rest of the time? What temp? The stock fans are programmed to turn on low speed at 226*F and high speed at 235*F.

Thermostat housing is on top of the water pump, and below the throttle body. Courtesy of Shoebox:

http://shbox.com/1/4th_gen_tech2.html#thermostat_change
http://shbox.com/1/tstat.jpg

The fans are turned on and off by the PCM (computer). The PCM gets the coolant temp from the sensor in the water pump housing. There is a separate sensor for the coolant temp gauge. That one is in the driver's side head, between #1 and #3 plugs.

Checking the sensor:

http://shbox.com/1/4th_gen_tech2.html#ect

Overheating is often the result of not completely bleeding the air out of the cooling system. Shoebox has that covered as well:

http://shbox.com/1/4th_gen_tech2.html#cooling
http://shbox.com/1/4th_gen_tech2.html#radflush

 

Thanks for all the good info Injuneer,

While driving it stays at or just above the the 1/4 temp line. When stopped at longer than a couple of minutes, such as in traffic etc it can raise up to the 3/4 temp line, just shy of the red zone.

Speaking of over heating in respect to correctly bleeding out the air. I refilled my radiator after changing out my Opti Spark Distributor (lots of fun).

While refilling and filling up the radiator I had the valves open and fluid never came out in a steady stream. Is this an indication that I still have air in the system or does that mean the thermostat needs to be replaced? And is it possible that the air valves can get clogged.

I checked the level on my radiator this morning and it is still full. Should I run the car up let it get warm and then open the air valves, will this help the air escape?

 

You could still have a little air in the system, but if it is a small amount, it will eventually purge itself with heat and cool cycles. You can try purging any air with the bleed screws when the system is pressurized at operating temperature.

Temps rise when you stop (and the fans are not on). That's normal.

 

Shoebox,

I understand it rises a little bit when the car isn't moving but I can't understand that it would rise from 1/4 of the temp gage to just under the red line at 3/4 the temp gage.

Plus I never here my fans on when the car temp gage is just under the red line. Wouldn't the fans stay on when I shut the car off if the temp gage was that hot?

 

The fans don't run when the car is off. They don't even come on until 226°, which is a bit over 1/2 on the gauge. The gauge may also not be totally accurate, either. Even when the fans do come on, the temp may rise a little more before the fans effect is noted.

 

I have the exact same issue with my 1994 Z28. It will almost redline at idle or below 20mph...but soon as I get to 40 or above the temp drops back to below half.

 

Do your fans work? Have you checked for codes? Was the cooling system properly bled to remove the air from the system?