[hemibadfish]

I have a 2005 GMC Duramax diesel and have recently been having a no start problem. Last week I parked my truck in the evenining, the folowing morning it would not start. It turned over great but would not fire. I checked the electrical connections under the hood and tried again, still would not fire, primed the fuel filter and tried again, still wouldn't fire. Finally had the truck towed to the shop. They hadit for the day and said the found a bad connection in the plug connections under the hood. Took the truck home, ran fine, next morning started fine and ran well all day. Parked it Friday evening, went to start it monday morning and same thing, turns over well but won't fire. I unplugged the connection they had told me about and retried after every check I made, wouldn't fire. Had it towed to the shop. They said after it was unloaded they tried it and if fired right up. Ran fine that afternoon, parked it that night and started it the next morning, ran fine all day. Parked it at night, next morning it wouldn't start. Repair tech came to house late afternoon, tried it and it fired right up. Truck is currently still at the shop as they have not been able to determine the problem. Anybody else heard of such a problem?? The truck does have an Edge chip in it, we removed it from the system and tried to start it several times when it wouldn't go and it still wouldn't fire. The GM shop could not find any codes on their scanner any of the three times to help with diagnosis either. Any help or suggestions would really be appreciated.

Thanks

 

[tref]

when my 04 lb7 did that sim. prob. i took it to the dealer they replaced a kimked fuel line on top of eng that goes to the pump but that did not solve the prob i simply started using the other ign. key truck has stsrted & ran fine since

 

[ob_1jr]

Have a look at the #2 and #7 injector harness, they are known for chafing and there is a TSB out for it. When is the last time you changed your fuel filter? Are you able to pressurize the system with the primer and not cracking the bleed screw? Those primer pumps have been known to go bad and cause problems.

 

[unclebob]

I had the same story, just the way you described it-the dealer could not find a problem until I had them park it on an incline. Two hours later the truck would not start-no fuel pressure. They said the problem is the fuel filter housing. They said it would take 2 days for part to arrive. I will let you know it this fixes the no start problem. My truck is a 2006 Duramax.

 

[Electric Boss]

Ok, I'm no mechanic & I'm sure you guys have it covered but if you all remember on the 02's they had an injector problem. My 02 had the defective injectors & it would do exactly as you are describing. It drove me crazy. The quick fix that usually worked, not always, would be to loosen the screw on top of the filter & prime it until fuel came out. Might try that.

 

[Canucktruck]

I have an '03 duramax (with 135,000 miles) that's doing the exact same thing. It had all new injectors installed last year under warranty, and has the (long ago) updated fuel filter housing. Every once in a while for no apparent reason, it will just crank all day, and never fire. Sometimes it's right after I shut it off, and sometimes it's when it's cold. Doesn't seem to matter if it's level ground or on a slope. I get it towed to the dealer, and it usually fires right up. The only code it's ever thrown was something to do with the injector pump harness so they checked it out, cleaned it, and sent me home. Was fine for 3 or 4months. I put a new fuel filter on it two weeks ago, ran fine ever since, then I go out yesterday morning, and it won't start. I can bleed and prime all I want, and it makes no difference. Now I'm missing a day of work today b/c I'm stranded 4 hours out of the city. I'm pretty methodical about trying to diagnose stuff. So far what i haven't had checked is the injector harnesses as mentioned above, or the return pressure. That's next. I'm pretty suspicious that it's not mechanical fuel starvation (pinched line), or air, as those problems would cause it to run bad or not start, on a continual basis. Like I said, it's very random, always out of the blue, and then the truck might run/start fine for 3 or 4 months. Any other suggestions from guys who have had this problem? BTW, the truck is completely stock, doesn't smoke abnormally, runs great once it's going. Could this be a ground issue? I did have trouble with my 4x4 a few years ago, and it turned out to be a dirty ground that was causing that problem. @ Hemibadfish: Sorry to highjack your thread. I would have started a new one, but I figured we might both benefit from what other guys have to say. Hope you dont mind.

 

[jackpot2594]

My father in law has a duramax that had about the same problem. When starting it would crank and crank without starting, finally it would start. Sometime it would start ok most of the time it would crank and crank. The dealer could not find anything wrong. He ended up replacing the entire fuel line from the tank forward. That fixed it . It now starts great. The dealer wanted about $400 for the FACTORY FUEL LINE REPLACEMENT he used a rubber line from NAPA for about $25. Must be from the salt on the roads?

 

[rtravis]

I have the exact same problem when it does start runs great all the power you need at this point i can't get mine to start anymore at all.

 

[jc1843]

Inspect the FICM wire harness at the passenger side of the alternator. The harness and wires get cut, and sometimes short to ground, by contact with the sharp corner of the FICM bracket.

The harness is tied down with a zip tie, cut the zip tie and look carefully at the under side. Insulate with a piece of heater hose.

This is a common problem for the LLY engine.

Everyone that has a LLY should check this now!

 

[[email protected]]

JC1843!

I joined this forum specifically to thank you for your march 2011 forum post regarding FICM wire harness. I was having a goofy no start problem, searching the net, filtering through irrational ideas and then i came across your post. Went out to my truck...sure as Shite, once I located what you described, cut the zip tie, turned over the taped harness, I could see shining metal wires and visible arching onto the brace. fixed that, hit the prime button a few times....back in business. Dude, you just saved me an awful amount of time and money!!!!!

 

[jc1843]

Thanks, GM should have had a recall on such a simple fix--- they finally did do a TSB for the techs.

Welcome to the Forum, be sure to read up on the "Ice Pick" fix.

 

[j-turner]

hey guys buddy came over tonight to finish up some paperwork for work might have been here an hr or so but his remote start fired his truck but only ran about a min or so and cut off now wont fire it turns over fine and is getting fuel... been reading a lot of posts and trying different things. neither of us are mechanics so we have no idea what FICM is nor do we know if we are checking the right harness.... any help would be great but will defiantly need simple and dummied down instructions lol thanks guys

 

[daylan869]

I have a 2003 Duramax have the LB7 in it I swap the LB7 for the LLY changed out all the wiring but the cab first time I tried it the truck started I shut it off I can't get it started any ideas? And it's not a fuel problem


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