Ford Repair Questions? Ask a Mechanic for Answers ASAP
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This is a common problem with the 1989 Rangers. The fuel pump relay is ground switch by the PCM ( computer) , The PCM sees key on and cycles the pump on and then waits to see the crank signel to turn it back on. If the switch leg wire ohms ok to the PCM , and the pump only runs when you ground it then you have a bad PCM. Replacing it will correct your problem.