2001 Tahoe - Hard Warm Start

[Ramsair]

Hello everyone,
I have read every post on multiple boards regarding this issue.
Most people say that the challenge stems from a fuel pressure regulator ~ well, long story short... I took a wild stab in the dark and just replaced that part today and my hard start is still there. The one good thing about the 2001, unlike the older tahoes is that the regulator is on the fuel rail on the drivers side - not under both intakes. (This is not talked about on any board)

In common with most posts, it mostly happens after it has been driven and then turned off, for as short as 10 min. or as long as a few hours.

The fuel pressure regulator part is 73$ out the door at Autozone - I will leave the new part in, just so I can feel confident that it will not be the cause for failure. So now the question(s).


Has anyone had this happen, if so what was your fix?

I have not had my fuel pump pressure checked - that will be next... At 85K I changed my plugs, flushed the radiator, the power steering system and put in a new fuel filter, because it was doing the hard start then - only not as bad - now it is worse and takes 3 to 4 turns of the key for the engine to start. I am at 88K now, the engine is the 5.3.

I don't think it is the fuel pump - car runs well, and does not hesitate up hills or under heavy acceleration. I am averaging 13mpg with AC on all the time (Arizona).


Any input??? Could it be the MAF? O2 sensor? By the way, I am not throwing any codes related to this issue.

Thanks in advance for any and ALL suggestions,

Chris

[horse482]

Had a '97 do the same thing, ended up being the coolant temp sensor. It is the sensor that tells the ecm what temp the engine is at. It is located next to your thermostat housing in the intake manifold.

[taillight]

Put a fuel pressure guage on and watch after you shut off the engine. It should hold pressure. If not the injectios could be leaking.

[MT-2500]

As Taillight said check that fuel pressure.
Check cold start fuel pressure.
Check engine running fuel pressure.
Check engine running on the road fuel pressure.
Then shut it off and watch for fast leak down.
Pinch off at rubber part or block off return line and check full pressure.
Later V6 and V8 gm engines should have 55-66 fuel pressure.
Cold start should be 55/62 lbs of pressure.
If you do not have full fuel pressure on a cold start the injectors will not squirt fuel.
Do not leave home without it.
Engine running should be 55/62 lbs pressure depending on engine load.
Full pressure with return pinched off should be 75-85 or more.
And if it has a fast leak down after shut off you have a leak.
If pressure does not come up with return line pinched or blocked off.
Go to fuel filter and hook a gauge direct to a line at fuel filter.
Pressure should come up to 75 or more and will hold after fuel pump is turned off.
If it leaks down there after fuel pump is turned off it is LEAKING BACK THREW PUMP CHECK VALVE OR PUMP MODULE LINES.
Post back your fuel pressure readings.
MT

[Ramsair]

Thanks for the ideas and direction - I will do the checks on the list mentioned and let you all know.

Chris