I have a 93 ford ranger 4x4 five speed 4.0. I just bought it, and it has some problems. I have no communication to the ecm with the scanner, and the check engine light is on. And the truck is running really rich, black smoke out the tale pipe and is missing too. and the fuel pump is running all the time even when you first turn the key on, And i can hear a hissing coming form the back of the block. What is going on with it, Do i need a new ecm?


Thanks, Dustin

 

Check all the fuses , then check for a vacuum leak , then check the fuel pressure regulator.

 

Pull the vacuum line off the back of the fuel pressure regulator. Is there fuel there? If so, then you need a new pressure regulator as the diaphran is breacked and your pumping fuel into your vacuum system and causing the engine to run rich. The miss would be causied by the excess fuel into the cylinders.