ok so i drive a 91 civic and when i start the car it runs fine for about 5-6 minutes and then it just shuts off. I've taken both my battery and alternator to advanced auto parts and auto zone. they both said the same thing. both parts were fine. so can anyone help me out with this please? thanks

 

Is your oil pressure ok? Secondly, if its not your alternator, it could be that there is something weird going on with your fuel system... I forgot the technical term, but its where the fuel evaporates before it gets to the engine. Perhaps if your injectors or something are really clogged and only a little bit of fuel is making it through then once the engine heats up it "vaporlocks" I know that sounds a little farfetched, but if you can't find out what's up then it might be something to look into. It might be a good idea to get your injectors cleaned out anyway.

OK, so if it really is your electrical system, then you should go a little further with a simple test to check the wiring. Start the car up and remove the negative battery cable. If the car shuts down, then there's something funky with your wiring.

 

check the ignition relay its probably overloading and pooping out.

 

werd main relay could be a culprit. seems our ef vehicles have a tendancy to go out without notice.