not starting

[redneck1572]

my 02 lb7 died 20 secondsx after i started it this morning... i took out the alternator and had it tested and it was fine.... what might be the problem???? it turns over but never starts???

[ob_1jr]

sounds like air in the fuel system. When's the last time you changed the filter? Did you try to bleed the system? That plastic bleeder screw could be cracked too. You don't have an Edge on the truck right?

[redneck1572]

I changed the filter bout three weeks ago.I couldn't locate the plastic bleeder screw. no edge

[JMD]

Originally Posted by redneck1572

no i couldn't locate the plastic bleeder screw. no edge

The bleeder screw is on top of the filter housing. Make sure it is not loose to start with, if it is tight, loosen it and pump up the system by pushing down on the "pump" which is near the bleeder. (the pump looks like a closed cylinder, about 1 1/2 inches in diameter) Pump until fuel comes out of the bleeder. Listen for air that might be escaping prior to the fuel coming out.

Once you get fuel through the bleeder close the bleeder and pump the pump a half a dozen times or so, then try starting the engine.

if the engine starts, then your fuel system is getting air in the lines.

[redneck1572]

will do thnx for the advice

[CHD]

I read the symptoms and replies in regards to the engine starting, then immediately quiting. Changed fuel filter, and pumped the primer multiple times after the bleeder screw was closed. Realized the bleeder valve was not completely shut and that there was still air in the filter and/or lines. Secured the bleeder screw with a screw driver and pumped primer a few more times, 'till I couldn't push down any more... engine fired right up. Thanks

[maxsn]

I started the engine in the morning after sitting for about 36 hours. It ran for a few seconds and stopped. I had just had the truck serviced about 3 days ago and had driven about 68 miles before parking it. I have the edge with juice, and disconnected it and tried to start it one more time but the engine turns over but will not start. 3/4 full fuel tank. Stuck in the mountains.

[rj18181a]

Hello, I am new here but hope someone can help. My truck is stuck here in Houston due to the hurricane and I am missing work daily where I was employed in Duncan Oklahoma.
It is a 2002 Duramak, bone stock, no chip.the 6.6 will crank up if I bleed the filter, turn key off and on 3-4 times, then crank for 45 seconds it will grab hold and run. It will start a couple times after that but overnight it leaks down so much I have to fill the bleeder screw up a couple ounces, then prime again. I replaced the filter, it only had 2000 miles on it but started with the easiest. I then bought a new bleeder and O ring (18 bucks from GM) still no luck. No fuel on the ground while running or sitting. I borrowed a Matco Determinator code reader from a friend and it shows last code as "Fuel rail pressure low on power enrichment" It shows no current codes, this is a past code. When running the datastream on the Matco shows fuel pressure around 6000 which is what it says is ok. Not sure about all this, have heard it was a pressure valve, the injectors, the O rings on the injectors, fuel filter bracket/primer. Really lost here, can anyone please help?
Thanks in advance
Ron jennings
RJ18181A@aol.com

[BigRedChevy]

What about the wif sensor? Did you possiblly overtighten it and crack it. Since the duramax works off of vacuum it is hard to trace down a leak, but you are getting air someplace. I would start with taking the filter back off and checking the orings on the filter and check the wif sensor for cracks.

Welcome to the site!!!

[rj18181a]

Thanks for the reply, the wif looks ok, just tightened it snug, swaped out filter and O rings are fine, still at a lost so far.