Hello, I've been trying to get a friend's comanche running, it is a 1991 4 cylinder 2 wheel drive. He replaced the old fuel pump and got a new one that was a little smaller, he made it work and wired it up and it won't work, you can't even hear it try to do anything with ignition on, we've hotwired the relay and tried everything obvious. is there a way he could have wired it in backwards or maybe it's not getting power, I'm hoping it is a common problem and someone knows, please help.