About a week ago i forgot to plug in my truck overnight and it got down to about 32*.
Went out to my truck to go to work, tried to start the truck and nothing. Just cranked and cranked and cranked. I didn't wanna hurt my starter, so I'd only crank for 5- 10 seconds and leave 30 seconds or so in between for it to cool down.

Well after out about 4 tries, I was about to give up but decided to try turning the key to on...wait until the glow plug light went out...turned the key off, then back on again untill it went out...then started. I still had to crank it for a good 5 seconds before I even started to hear it try to start, it finally did start, but then imediately shut down. Hmmmmm
So i cranked one more time and it acted a lil like it didn't wanna run, but quickly ran like normal.


Made sure I pluged it in every night and it started like normal all but one or two times in 2 weeks. These times the truck would start...then die...then start up again the 2nd try.
I've also notice a small loss of power... but that might be in my head tho lol


Well today 70* and sunny, went to start my truck after only sitting for 16 hours or so.
Would not start. Took about 50 seconds of cranking before it did. (With pauses!)

I just checked the fuel prime and its primed.



In my searches I've found that people have attributed this to either Glow plug issues or injector failure.
Any way to decifer between the two? i dont have a scanner to check the return rates. Also all these post I found were of people who never got theirs to start...not intermittent issues like mine


BTW: 56,000 miles, 2003 lb7. stock

Thanks guys.

Willing to bet that it's injectors.

How many miles?

Willing to bet that it's injectors.

How many miles?


Oh sorry, 56,000 miles

Had first set of injectors done at 22,000 and the second set at 28,000.

Installed Nicktane Kit, have a 106,000 and no problems.

One thing that is nice is that our injectors are covered to 200,000.

Have you checked the fuel housing for cracks? I would take it in and have it looked at. Should not be doing that with that kind of mileage. When was last time the fuel filter was changed? What did the junk that came out of it look like?

Have you checked the fuel housing for cracks? I would take it in and have it looked at. Should not be doing that with that kind of mileage. When was last time the fuel filter was changed? What did the junk that came out of it look like?

I've only had the truck for 2000 miles. I dont know the last time if was changed unfortunately.

Everything fuel related is clean though, if there was a crack would it leak fuel?


Also, for those who have had injector issues, what where the symptoms and could you smell fuel in the oil?

Seems like alot of people are having starting problems, there are like 4 active thread on it. But mine is the only one thats intermittent. wierd

UPDATE


Forgot to plug in the truck again overnight...16 hours it sat in 40* weather.
Started right up on the first crank.
WTF?

These problems are the worst because they always happen at the worst time, but can never be duplicated at the dealer.

So no one here has a guess, or experienced the same problem as me? (that my truck starts perfectly normal 80% of the time, and the 20% of the time that it wont start period, the conditions are never the same[hot and cold]:help: )

Why are you plugging it in when its still warm? Really dont need to plug these trucks in till around 0*f.

How do you know that the truck didnt loose prime?

If it dosnt start and you push the primer till it becomes hard to push will the truck start?

Why are you plugging it in when its still warm? Really dont need to plug these trucks in till around 0*f.

How do you know that the truck didnt loose prime?

If it dosnt start and you push the primer till it becomes hard to push will the truck start?



I plug it in 1 because the owners manual says "below 25*, plug in for 4 hours, below 0*, plug in for 8+ hours."
30 is real close to 25...so whats it matter?
I hate cold starts anyway, oil is thick and flows very slow to critical bearings, engine ins't running optimal...plus i never use anything more then ~1/4 thorttle and no more than 1500-2000 RPM on any of my cars until they are fully warmed up.
With the duramax, it gets warmed up just as im pulling into work 18 mins later. If its plugged in, it warms up much faster. maybe 3 minutes or so.

Perfsonal preference i guess.

To check the prime, i simply just removed the plug and barely touched the primer and there was fuel there...this was after it sat overnight.
I would find it very odd that there would only sometimes be an air leak and sometimes not in the fuel lines.

Next time it dosnt want to start, attempt to prime it and see if it starts right up. Really without putting a scan tool on it and seeing if its building pressure at initial crank, its all guessing.

Also change the filter if you havnt already.

Had the exact same issue, with the exact same symptoms. If it got below 40*F and I forgot to plug it in all night, I was screw*d. Every time I checked for loss of prime, fuel was right there at the bleed screw.

After eight new injectors (at 39k miles), starts better than it ever has!

Everything fuel related is clean though, if there was a crack would it leak fuel?


Not necessarily. I had a gasket not seated correctly in the WIF sensor in my fuel filter, and it caused symptoms very smiliar to yours in my truck; it was allowing air into the line SOMETIMES, but not all the time. Check your gaskets and check for leaks.

another thing i just realized, check to make sure your anti-theft isnt cutting off the fuel. mine started acting up out of the blue with no explanation.... sometimes it would start with no problems, sometimes i had to crank it 15 times before it would start, before i realized to look at the dash and check for the theftlock indicator...