2001 fuel pump/fuel problem

[BSracer]

Fuel pump went out, motor stopped on highway, lucky enough to coast off an exist ramp. Towed the truck to a local shop and received a new pump. ALL was great for the first week. Then check engine light came on. I though OK O2 sensor upset because the truck was now running great. It did not clear itself in time and began to run poorly. Got the truck back into the shop and had the O2 replaced. Now the truck will not start quickly. Cranking ON and on and on until it is running. I take back to the shop and am told the check valve is not holding in the new pump. After 3 weeks I finely get a spot back in the shop for a replacement pump. I get the truck back and am told it is not the check valve it is a part of the injection system in the manifold. Is the reasonable to you. I have not way to know the pump was replaced a second time. I am through with the shop. Could it be the injector block in the manifold?

Pardon my rambling.

Do I replace the fuel pump or the injector block in manifold first?
Could I place a inline check at the pump? Any one know of such a valve to use as a tester?

[j cAT]

Originally Posted by BSracer

Fuel pump went out, motor stopped on highway, lucky enough to coast off an exist ramp. Towed the truck to a local shop and received a new pump. ALL was great for the first week. Then check engine light came on. I though OK O2 sensor upset because the truck was now running great. It did not clear itself in time and began to run poorly. Got the truck back into the shop and had the O2 replaced. Now the truck will not start quickly. Cranking ON and on and on until it is running. I take back to the shop and am told the check valve is not holding in the new pump. After 3 weeks I finely get a spot back in the shop for a replacement pump. I get the truck back and am told it is not the check valve it is a part of the injection system in the manifold. Is the reasonable to you. I have not way to know the pump was replaced a second time. I am through with the shop. Could it be the injector block in the manifold? Do I replace the fuel pump or the injector block in manifold first?
Could I place a inline check at the pump? Any one know of such a valve to use as a tester?

the fuel pump testing is done when the pressure guage is attached to the fuel rail test port. a 2001 5.3L engine should have 60-62 psi engine off , key to ignition on. then the pressure should hold. now lets say the pressure is low and does not hold. then you make a connection at the fuel filter line under the vehicle near the fuel tank . in other words the fuel pump is now only feeding the pressure gauge. key on engine off [obviously] the pressure go up to at least 65 psi maybe be much more. if the pressure holds then you have a bad fuel regulator or injectors leaking down.

if the pressure does not hold and is of below spec pressure then they sold you a defective pump/airtex cheapo fuel pump. make sure you only use an ac delco or delphi pump. also they must solder and crimp any connections to the connector at the pump if any wiring is screwed with .

good luck this is not that hard to figure out with the correct tools/info.......

[BSracer]

j cAT Thanks I have a fuel pressure gage, I will find a quick connector for the pump. May have one with the gage set.

[BSracer]

Finely got the parts together to test the pump at the filter. I have 85lb at turn of key but in 15 minutes it falls to 55. Do I go argue with the shop?

[MT-2500]

Originally Posted by BSracer

Finely got the parts together to test the pump at the filter. I have 85lb at turn of key but in 15 minutes it falls to 55. Do I go argue with the shop?

If you have 85 at fuel filter with a 2 second key on prime up.
That should be enough to start and run the truck.

What is the pressure at test port on engine?
If it is low or high has a fast leak down you have a bad fuel pressure regulator or leaking injector.
Pull vacuum hose off at regulator and look for gas in it.
Then block off return line and if pressure comes up to 85 or more the fuel pressure regulator is bad.

[j cAT]

Originally Posted by BSracer

Finely got the parts together to test the pump at the filter. I have 85lb at turn of key but in 15 minutes it falls to 55. Do I go argue with the shop?

like I stated before and also member mt2500. you now appear to have a regulator or injector issue.

85 psi is good. pressure holds for 15 min this is all good for pressure at the pump only output .