My 1991 Crx dx with a mpfi swap is not getting fuel pressure. The fuel pump will not prime so i checked if there was power going to pump. I checked yellow/black wire for power and used black as ground. I was told yellow/black is main power. Can anyone tell me what the other wires are for? So now im thinking it must be the main relay but i have done some research and everyone is saying that the relay goes bad in heat and my car is in wv currently where it is freezing. Any ideas as to what else it could be or how i could no for sure without taking out the main relay as my car is stuck up at a friends 300 miles away from me.