My service engine soon light is coming on soon after I start up my 95 z28. I can also hear a fan kicking on and its pretty audible if I dont have the radio on. The car never even gets close to overheating but the light and fan still come on. A friend suggested that it might be my transmission overheating from lack of tranny fluid so I got that flushed and topped off but it didnt help. If I sit at a stop light for more than 5 minutes the light and fan go off, but as soon as I start going again they both come back on. Does anyone know what it might be?

 

Depending on the trouble code the fan may be forced on to protect the engine. Get the PCM scanned and find out what the complaint is. It may be nothing much or it could lead to a costly problem

 

I bought an obd aldl cable to connect to my computer but the thing never works. Does anyone have a link to drivers and an app that actually work?