man i'm sure this question has probably been asked before, but i have a 95 Z28. the fan and service engine soon light come on at the sametime. they both stay on when i'm driving but will go off when i'm at a stop light or anything like that when i put my foot on the brake. what could be causing this. i need some help.....lol......

 

You need to get the car scanned & see what it is complaining about. It could be something serious or something minor. The fans will go on to protect the engine when the SES lite goes on. If I were to guess I would check the EGR valve, but it could very well be something else.

 

what is the EGR valve? what does it do

 

The EGR stands for Exhaust Gas Recircuation. It is located at the rear of the intake manifold. The valve is controlled by the PCM, and should open only at cruising speed and it should shut off at idle and wide open throttle. Its purpose is to reduce Nitrogen Oxide (NOx) emissions by introducing a small amount of exhaust gas into the intake, and thus cooling the combustion temperature. This also allows more spark advance at cruising speed for better fuel economy.