2000 Suburban 248,000 miles
A few days ago our Suburban began dying periodically at low speeds under 30 mph. Had the codes pulled and came back with 3 codes relating to the EGR valve which we replaced. We also replaced the fuel filter and Fuel Pressure Regulator as it had fuel in the vacuum line. Since replacing the regulator the fuel pump sounds like it is working overtime and very hard.

Testing the fuel pressure with the key in the on position immediately reaches the correct psi (60) and the fuel pump turns on for a few seconds but then will not hold the pressure and pressure quickly falls. Fuel pressure while the engine is running holds at 52 psi and the fuel pump runs very loud and continuously.

The vehicle has not died since the EGR valve was replaced and continues to idle very nice with no RPM fluctuations

We also have codes related to the catalytic converter and have had those for over a year, but have not replaced the converter.

Any ideas on the fuel pressure not maintaining and the pump working hard and loud?

~Shannon

 

Sounds very much like a fuel pump to me...