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Help diagnosing fuel pump problems


New Member
Hi guys I have a 93 5.0, fuel pump was acting up, when turning key to on position it would continuously run instead of just priming, changed pump & the same thing is happening, any help on what's going on would be greatly appreciated.


Active Member
That is typically caused by a bad ecm or bad ignition switch. Both are common issues. I would check the ignition switch first. You will need to visually inspect it to see if the plastic side is separating from the metal side.

If the ecm is bad, you may want to consider having it repaired. They're getting hard to come by. If you can do the repair yourself, they can usually be fixed with a couple bucks worth of parts.