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Died, Wont Start, How Much Fuel Pressure Is Needed?


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Posted

Dear Techs,

As I was driving my 98 1500 yesterday evening, I noticed all of a sudden that it started to sputter a bit. I noticed a few surges, decided I'd pump the gas once to see if I could get all cylinders to fire good for a sec....as soon as i hit it...it died. I soon found myself coasting into a parking lot. My dad had the fuel pump go out in that truck about 3 years ago. He said the mechanic then told him that even though the pump will pump, if there is not enough pressure then it is useless. Any truth to that? We disconnected the fuel line from the filter and there was gas flowing, but it didnt seem to be very pressurized, just kinda dumping out of it. Any thoughts on whether or not that the pump is the problem before we tackle it ourselves?? Thanks a ton.

 

Jeremy

Posted
Dear Techs,

As I was driving my 98 1500 yesterday evening, I noticed all of a sudden that it started to sputter a bit. I noticed a few surges, decided I'd pump the gas once to see if I could get all cylinders to fire good for a sec....as soon as i hit it...it died. I soon found myself coasting into a parking lot. My dad had the fuel pump go out in that truck about 3 years ago. He said the mechanic then told him that even though the pump will pump, if there is not enough pressure then it is useless. Any truth to that? We disconnected the fuel line from the filter and there was gas flowing, but it didnt seem to be very pressurized, just kinda dumping out of it. Any thoughts on whether or not that the pump is the problem before we tackle it ourselves?? Thanks a ton.

 

Jeremy

 

 

Fuel Pressure Spec should be 60-66 psi

Posted
Dear Techs,

As I was driving my 98 1500 yesterday evening, I noticed all of a sudden that it started to sputter a bit. I noticed a few surges, decided I'd pump the gas once to see if I could get all cylinders to fire good for a sec....as soon as i hit it...it died. I soon found myself coasting into a parking lot. My dad had the fuel pump go out in that truck about 3 years ago. He said the mechanic then told him that even though the pump will pump, if there is not enough pressure then it is useless. Any truth to that? We disconnected the fuel line from the filter and there was gas flowing, but it didnt seem to be very pressurized, just kinda dumping out of it. Any thoughts on whether or not that the pump is the problem before we tackle it ourselves?? Thanks a ton.

 

Jeremy

 

 

Fuel Pressure Spec should be 60-66 psi

 

 

 

I just checked the pressure on my truck at the valve on the crossover tube just beneath the top plastic cover on the engine and it reads 50 psi with the engine not running and 47 psi with the engine running. My truck seems to run ok, it has been taking more turns to start it cold. Is this pressure a problem, and should I replace the pump, the regulator or both, how would I know if it's the regulator or the pump ?

2001 Silverado 6.0 2500HD

Posted

To verify if it is the regulator you will need to plug up the return line from the regulator and recheck pressure. if the pressure dose not change then it is a fuel pump.

Posted
To verify if it is the regulator you will need to plug up the return line from the regulator and recheck pressure. if the pressure dose not change then it is a fuel pump.

 

If I replace the regulator along with the fuel filter and the pressure is still 47psi with the engine running, then would it be safe to say the fuel pump is weak ?

Is 47psi below the specs for this truck ? I ask this because the truck seems to run ok with 47psi fuel pressure.

Posted
To verify if it is the regulator you will need to plug up the return line from the regulator and recheck pressure. if the pressure dose not change then it is a fuel pump.

 

If I replace the regulator along with the fuel filter and the pressure is still 47psi with the engine running, then would it be safe to say the fuel pump is weak ?

Is 47psi below the specs for this truck ? I ask this because the truck seems to run ok with 47psi fuel pressure.

 

 

 

You need 55 psi or more for the truck to run correctly

 

If you replace the fuel pressure regulator and it still reads under 55 pai while running then yes it is the pump.

Posted

changed the fuel pump.....didnt fix it. Dad said he started it once, idled so so, when he gave it gas, it felt like it just bogged down, then died. wont start again. we put a new battery in there, the tester is showing that it's got full voltage, but the dash isnt showing a good charge. any ideas out there? i think he's gonna call a tow truck in a few hours if we dont come up with a great idea soon. thanks for the help so far

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