white89gt

The diaphragm is what leaks. It has to be under pressure, and the fuel eventually evaporates, or is consumed by the vacuum pulling it into the intake.

So, in order to get to this condition, you need to let the pump pressurize the system, and pull the vacuum off. And yes, it will still run without the vacuum line.

SCtruck

Okay, I put in a new fuel pressure regulator. I let the truck run for more than 20 minutes (being run or driven for a while seems to trigger the problem. Cold starts or starts after running only a few minutes are no problem). Would not start. After it sits awhile, it will start again. I don't regret putting in the new pressure regulator. I would have always wondered if that was the issue. I have ordered a fuel pressure gauge so I can check the pressure at different stages and when it doesn't start. My next inclination is to replace the fuel pump. Any alternative ideas?

Jbrew

Didn't realize you wern't checking pressure, that would been the first step. Yea the pump is most likley going out, that's what they do, they begin to freeze up off and on at start. Without a gauge you can verify by smacking the tank with key on and listen for the pump to energize.

Should of been "crank no start" thread.

SCtruck

Also read on another thread on this forum about a similar problem that was solved by replacing the crankshaft sensor. What do you think?

The truck is parked under a large oak tree in my yard. I am literally and figuratively a shade tree mechanic.

Jbrew

If it was the crank sensor, it wouldn't run at all.

SCtruck

Good to know. Thanks.

I have an OBD II reader with a phone app that I got to check codes. There are no codes showing and no check engine light on. However, I do have these readings taken at idle with a cold start. I have no idea whether they are good or bad for the most part. Vacuum 14.7, Load 29, MAF 4.9, STFT1 -.8, Intake 37, Timing advance 14, Trottle 19.2, Revs 767. There was no number for fuel pressure shown but I have ordered a separate gauge.

BareBonesXL

Does it smell like a flooded engine?

What happened to the old basics of check for spark, check for fuel?

SCtruck

Sometimes when the truck has not fully recovered, it will start but will run extremely rough then stop running altogether. Wait several more minutes then it starts with no problem.

Want to know what is embarrassing? When you get to the tire dealership, pick out and pay for your tires, then your truck won't start and the poor tire changer guys have to roll floor jacks out to the parking lot to change the tires. That's me.

mbb

Turn key on , not to start, for several sec before starting
you can hear hum of the fuel pump, then it stops.

See if you dont hear that......when it doesnt start.

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SCtruck

Since I've posted this, I've seen 2001 Crank, no start and 2002 Crank, no start. Mine should have been Crank, no start too. I've seen others of these in the past. What gives?

I have a fuel pressure gauge now but haven't checked it yet. Fairly certain that I may tackle changing the fuel pump myself with one helper. So advise me - I've never done this but I do have some slight mechanical experience. And I have a computer and watch YouTube! Is this something a 60+ year old man with semi-semi-mechanical skills should tackle on his driveway?