97 Suburban won't start

[timber]

The suburban has been harder and harder to start, turns over, and coughs, but won't start often. Fuel rail pressure is 50 in the on position, and I think 56 When I can get it started to Idle. Is this for sure the fuel pump? How do I troubleshoot before buying more parts?
Just changed the fuel filter, and still the problem remains.

 

[Molson02536]

The suburban has been harder and harder to start, turns over, and coughs, but won't start often. Fuel rail pressure is 50 in the on position, and I think 56 When I can get it started to Idle. Is this for sure the fuel pump? How do I troubleshoot before buying more parts?
Just changed the fuel filter, and still the problem remains.

Start with the simple and check to make sure your fuel sending unit (fuel pump) still has a good ground. It's common for our older SUV's ground wires to corrode which leads to a bad ground which in turn will cause a poor current flow that equals low voltage.

Just follow the wire harness to your sending unit at the gas tank and work your way back to where the ground wire is attached to the frame. At worst, yes your fuel pump is worn out and will need to be replaced.

GM trucks and SUV’s from 1995-2002 equipped with the 4.3L, 5.0L, 5.7L engines equipped with the Central Sequential Fuel Injection (CSFI) may encounter injector plugging. The fuel system pressure is critical, as the pressure range must be between 60-66 psi with the fuel pump running and the engine off. Pressure below 60 psi will usually result in a no-start condition, or the system will be lean and will barely run above idle, and DTCs may be set.

Keep us posted and be safe
Molson02536