When a ground wire does not make a good contact, can it have the affect of damaging the fuel pump?
I own an automotive repair facility in Georgia. The purpose of this letter is to get opinions on a procedure that we did on a 2002 Monterro Sport. Customer brought truck in by tow for a no start. After charging the battery we could crank over the engine but it would not start. Next, to see if it was a fuel, electrical, pcm, theft system, ignition switch or some mechanical issue. Sounded like it had compression so we moved on to fuel as the suspect. With a few sprays of carb cleaner we could get the engine to run for a few seconds. With this we are pretty sure of a fuel issue. After removing tank and then pump, we were able test the pump by energizing and grounding to a 12 volt battery. Pump would run for about 1 second before it would stop. It seemed like it was binding internally. Put in new pump, replaced tank, cranked and truck ran fine. Test drove and called customer to pick up. 2 hours after customer drove away, she called me and said truck would not start. Truck is towed back and we began to check and double check. We narrowed our search to the fuel pump relay in the kick panel and replaced it. Truck started and ran fine. Test drove may times to make sure of repair. Customer, again, drives away. About 4 weeks later I get a text from the BBB saying that the customer wants all their money back. She said she drove the truck for 2 weeks and then it would not start again. She then had the truck towed to the dealer and they said that they found a ground wire that was bad. They made the statement that the fuel pump and pump relay was not the problem. Our position is "yes" a ground wire could be an additional problem, but because of the test we did to the original fuel pump it was confirmed bad. The dealer of course had no access to the original pump and therefore could not rule out its failure. What do you think of our procedure and is it possible that the fuel pump failure could cause the pump relay to malfunction and also cause damage to ground wire?