'99 Tahoe 5.7L, starting problem

[hd_ryder]

My '99 Tahoe 5.7L is not starting easily for the last few weeks. It's not my daily driver.
I replaced the Fuel Pump in June 2010 with a Bosch unit. Before installing that pump, the only way to start it was spray some starting fluid in the throttle body. That is not working this time.
Now it will turn over, but not fire really. Sometime the motor will still be rotating, lumping a few rotations, for a little while after trying to start, but I can't hear it and I will get starter clash when I try to start it again. Not good.

When it does occasionally start, it seems to run pretty well, with no missing.

The cap, rotor and wires are only about a year old or so, and have a life of 5-year warranty at AutoZone, so I will change them next. I may also change the coil, as it probably is the original.
Looking on RockAuto, they do not list a Fuel Pressure Valve that I see, so it may not have one?

How about Crankshaft of Camshaft positions sensors? Could they be an issue?

Any other ideas?

Thanks for the help.

 

[lesterl]

Check fuel pressure. If that is good, suspect Crank sensor....

 

[hd_ryder]

Can you tell me where the Fuel Pressure Regulator is located on the '99 5.7L?

Thank you for the help.

 

[lesterl]

FPR is in the intake manifold.... Check the fuel pressure at the schrader valve before you tear into it. Checking the fuel pressure is good as you used a non OEM pump, and usually that isnt a good sign....

 

[hd_ryder]

lesterl, thank you for the info. Do you recommend an AC-Delco fuel pump, if the f/p is bad? I just checked with Advanced Auto parts where I bought the f/p in 2010. It has a Limited Lifetime warranty, but the part number has been discontinued, so they will have to give me another product. I will probably have to pay more for the AC-Delco unit.

Do you know what the typical symptoms are if a Crank Position Sensor is bad?

Thanks for the help.

 

[lesterl]

Your symptoms could be either, or neither, that is why you need to put a test guage on the service port to test fuel pressure, then check the fuel pump relay, then check power at fuel pump, before condeming the pump......

 

[hd_ryder]

I just put a Fuel Pressure gauge on the fuel line port at the back end of the upper intake. The vehicle had been sitting for over a week or more, and the first reading was at 60psi. The second and third readings came in at 58psi.

That appears to be at the low end of the 60 to 66 psi specification found in the Haynes Repair Manual.
From my understanding, since the reading was not above the 60 to 66 psi spec, it would appear the fuel pressure regulator has not an issue. Would that be correct?

Last time I had to replace the fuel pump in 2010, I could get the truck to start with spraying starting fluid in the throttle body. This time that does not appear to be working.

Any suggestions of which way to proceed in trouble shooting now?

Does the low pressure reading indicate the fuel pump is most likely the problem?

Thank you for the help with this problem.

 

[lesterl]

If it isnt starting with starting fluid, check ignition and compression. Fuel pressure sounds ok/ acceptable. Suspect Coil, coil wire, cap and rotor, crank sensor, pcm, ign switch, etc.

Check fuses, check for spark, check plug wires.....etc.

 

[hd_ryder]

Before going on to the step of replacing the CKP sensor, I replaced the Duralast distributor cap and rotor button kit from AutoZone, which had a 5-year warranty. They were less than a year old, but I figured replacing them for free under warranty might not be a bad investment in my time. After replacing them, the '99 Tahoe 5.7L started right up! I hear those Bosch made Duralast products are really not the best parts to put in GM vehicles, even though they are priced well, and have a decent warranty.

 

[lesterl]

Bosch made products in general suck, appliances, parts, etc....