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Discussion Starter · #1 ·
Hello everyone. I know this has been discussed many times, but I can't find my specific issue. Truck is a 03 LB7 with 260k on it. I do the fuel filter religiously every oil change because of these pesky injectors. I have also had to replace the passenger side bank of injectors in the last 10k miles. Over the past few months it hasn't liked starting when it is hot (maybe 3-6 seconds of cranking before start). Average of 100* days give or take. So I parked it for a few weeks and drove my other vehicle. 2 weeks ago I go out to start it when its cold and about 80* outside, and it takes about 3-6 seconds to start. Then just yesterday I was pulling a trailer and after dropping my load it would not start at all. I decided to let it cool down for about a half hour and for the first time checked the prime on the filter head. It was not primed so I pumped it about 20 times until it got hard and then it finally started after about 10-15 seconds of cranking. I then began to notice a moderate amount of smoke that was light colored blowing past my window when I was at stop lights, and the truck idled like shit.

The filter head has a minor leak when I pump on the prime button and really force it down when its already hard (but it has done that since I got the truck 35,000 miles ago). I have looked into the filter head rebuild, but it just doesn't make sense to me.

My question is; can bad return rates on fuel injectors cause a truck to lose prime? But in the same thought, wouldn't bad return rate not cause smoking at idle? My logic is it has to be one or the other, either bad return rates or stuck open injector. In that case why would my truck be a hard start, lose prime, and be smoking??? Torque pro cant read my balance rates because the truck is not attempting to balance anymore since they are so far out of whack. You can feel when the truck stops trying to balance them.

Any help is appreciated. Thank you.
 

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Discussion Starter · #3 ·
Decided on replacing the injectors. The last 4 are in the head currently and will be finishing up today or tomorrow. I will update when finished. Also, I decided to rebuild the filter head and examined all of the rubber fuel lines on the engine and replaced them. They pretty much all looked terrible!

Additionally I had a second questions if anyone else looks at this thread. Number 8 injector I could not get to "pop" into the injector cup. I lubed up the big O-Ring and pushed it into the cup as hard as I could. I meticulously cleaned the cup and made sure the O-Ring was lubed properly. All the others had that "pop". I figured it was fine when I yanked on it and it wouldn't come out of the cup. I then took a flashlight and looked where the O-Ring seats in the head, and it looked identical to the other 3 injectors that had popped in. I torqued the hold down bolt to 37 ft-lbs and figured it good. Now Im stressing about it. Hopefully all is well.
 

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Discussion Starter · #4 · (Edited)
For those of you reading this in the future, Injectors have fixed my issue from what I can tell. I finished tonight and drove the truck about 5-7 miles home with no issues. I started it and turned it off about 4 times in between a few test drives and let it idle for about 20 minutes. No smoke AT ALL! Seemed to start with no issues as well, no prolonged cranking. I am home for the evening, but will update if I run into any issues. I have about a 500 mile round trip planned this weekend. Assume no news is good news in regards to my original post. The truck runs better and has more giddy up then it did when I bought it approx 35,000 miles ago. Here's to another strong 150k miles!

EDIT: I also don't know how much of an issue those cracked fuel feed and return lines were, but they were TRASHED. Anyone in the future please look at your fuel feed lines very closely as well. I was blown away mine were not leaking.

Thanks yall
 

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If you will, please share the approx cost to solve your problem. I assume you did all the work yourself??
 

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Discussion Starter · #6 ·
Still no issues today. No leaks at all and it starts up great. The primer on the filter head is not "hard" after I drive the truck and turn it off, but it no longer has no resistance like it used to. No smoke at all. I did all the work myself, and it took about 25 hours total I would say. Around $3400 total including all NEW injectors and high pressure lines + the rubber lines and all gaskets, sealant, misc stuff. It may look scary but it really is not that bad! Just take your time and clean out the banjo bolt allen wrench holes with brake parts cleaner/compressed air!! Also in my PERSONAL opinion the 11 foot pound torque spec is a bit of a joke. I did them by feel.

JJ
 
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