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First of all it just a guessing game if you don't have a fuel pressure gauge on this. If you can get a hold of a gauge you can isolate the fuel pressure drop of either the supply side or the return side. If you cant get a hold of a gauge and see no external leaks or drips from the injectors it could be the pump check valve. But if does it on either tank its not likely. I know you said the TBI unit was rebuilt but my best guess would be the fuel pressure diaphragm seat. They are a highly polished seat that mates to the casting in the throttle body to close off the fuel return to the tank. If it is not seating good from say a burr it could be bleeding off.
for grins hook a jumper wire from battery to the 3" red wire on the fuel pump relay. this will bypass the ecm and energize the fuel pump. see how it starts and compare that to the noise you suspect is the fuel pump. this will energize the the fuel pump even with the key on
Quote from: Irish_Alley on May 29, 2019, 04:44:05 PMfor grins hook a jumper wire from battery to the 3" red wire on the fuel pump relay. this will bypass the ecm and energize the fuel pump. see how it starts and compare that to the noise you suspect is the fuel pump. this will energize the the fuel pump even with the key onGo from the positive side of battery to the red jumper line Sent from my iPhone using Tapatalk
I have to say that this is what if frustrating: no follow up and no resultsIrish suggests bypassing power so you can listen to the pump to see if there is a difference. That is huge in analyzing what is going on! Since you have changed the pump we will never know unless you try again. Have you looked for tubing issues that may have blockage, creating a vacuum that the pump has to overcome?
Sorry if I came across as a butt head, my observation is across the board, not just your issues. On the tire issue, have you looked for a bent rim? Easy to miss.