Fuel Pump Bad?

[kennythewelder]

I replaced a fuel pump in my 97 several years ago. It was a cheap pump. It went out within 3 months. Thats why I said use only AC Delco or Delphi pumps. I have a Delphi pump in it rite now. This truck is my daily driver. I had had the same p Delphi fuel pump in it for about 5 years. Still have 62 PSI with key on, before starting. This is when the fuel pump cycles for 2 seconds. At this point is where the fuel pump puts out over 60 PSI. When the fuel pump gets old, the impeller gets worn, and cannot put out enough pressure to start the truck. The popet valves need this much pressure to flow enough fuel to start up the engine.

 

[evilunclegrimace]

What do you mean by dead head?

Pinch off the return line so that the fuel pump will build the maximum pressure that it is capable off. This takes the fuel pressure regulator out of the equation and will tell you if the pump is able to provide the proper pressure to run the truck

 

[kennythewelder]

Fuel lines on a 5.7L vortec both supply, and return are steel. There is no rubber line to pinch off, until you get to the top of the fuel tank.

 

[fancyTBI]

I always see threads on fuel pumps going out. I replaced the stock one in mine at 300K. Most be an oddity.

Any-rate, could be fuel pump, but also filter like others said. If you let it get low recently and the pump could’ve sucked up some crud and it’s blocking the filter, doing its job at least! And like others have said, name brand only. Do not skimp out or else you’ll be using that roadside assistance again.

 

[454cid]

I always see threads on fuel pumps going out. I replaced the stock one in mine at 300K. Most be an oddity.

You have a TBI engine, which doesn't require as much fuel pressure.

 

[454cid]

Fuel lines on a 5.7L vortec both supply, and return are steel. There is no rubber line to pinch off, until you get to the top of the fuel tank.

That's odd. I would think the engine movement would crack solid lines. I have rubber lines going to my 454.

 

[454cid]

The truck has 258k on it and the pump has supposedly been changed before. I would use a fuel pressure gauge if i had access to one. None of the auto part stores around here do tool rental and there's no harbor freight within 50 miles of me.

You don't have an Autozone? If no one will let you borrow one, then buy a pressure gauge from the parts store... or Amazon.

 

[kennythewelder]

Yea, you would think there is rubber in the lines, but its only above the tank. I guess the steel lines have enough flex in them, IDK.

 

[kennythewelder]

Here is a pic of the lines on the engine. These 2 lines screw into 2 more steel lines.

You must be registered for see images attach

 

[Trenton]

I replaced a fuel pump in my 97 several years ago. It was a cheap pump. It went out within 3 months. Thats why I said use only AC Delco or Delphi pumps. I have a Delphi pump in it rite now. This truck is my daily driver. I had had the same p Delphi fuel pump in it for about 5 years. Still have 62 PSI with key on, before starting. This is when the fuel pump cycles for 2 seconds. At this point is where the fuel pump puts out over 60 PSI. When the fuel pump gets old, the impeller gets worn, and cannot put out enough pressure to start the truck. The popet valves need this much pressure to flow enough fuel to start up the engine.

Oh yeah im not using any other pump with the failure rate on these pumps. I only use Delco or Delphi anyway with whatever I buy for my truck.