I have a '96 camaro rs that overheats when I'm sitting in traffic. I changed the antifreeze because the previous owner went and mixed green and dexacool fluids so it was kinda clumpy, also changed the thermostat. while I was letting the car run after swapping fluid i could hear the fan run but I cant hear it run when I'm sitting in traffic. Was wondering if it might need a bigger electric fan since there is so much room between the motor and fan.

 

your going to need to flush and backflush the radiator and heater core a couple times. it may be that they are not savable. that stuff clumps up and sometimes you cant get it out. make sure you bleed the air out of the system a couple times till you get no more air.

 

I agree with craby. Definately flush your system. One easy way that I have found to do this is loosen your radiator drain plug, not completely but where it has a pretty good stream flowing out. Then take regular h2o and pour into the radiator cap with the engine running, this will cycle the fluids through your coolant and heating system while draining some of the old junk thats in there. Do this until you notice nothing but clear water coming out of the drain, and under no circumstance let the radiator run dry!!! Keep on pouring until it runs clear from your drain plug then shut your engine off and loosen the drain plug completely to let all of the water run out, let it sit for a few minutes to ensure that all the water has backflowed back to the radiator. Then pull your lowest radiator hose and check for gunk. Also you may want to check your thermo housing hose above the water pump. Tighten everything back up and fill with coolant. Hope this helps. If a system flush doesnt fix your problem, look into heater core or head gasket issues.