Having issues with a friend's 1987 Ford Ranger 4x4 2.9L It has a rough idle, just randomly started doing it. We would like to be able to read the codes, but the code reader is broken on the truck. We have the three bare wires and no clue where to plug them into the scanner. If anyone has a ranger like this I need to know where the wires go and it would be a huge help if you could tell us.