LB7 2003 smoke at idle
 

In the last couple of weeks I notice some blue smoke when I am idling. It only happens when idling and engine is warmed up. I have 80,000 miles on truck and this is the first time I am having trouble with it. I changed oil and filter and also fuel filter. I keep on looking at the oil level for possible fuel leak into sump. No change. However, it might be too early to tell because I only have 70 miles on it since the last oil change. I use the right specifications and viscosity for the oil. The air filter is an after market K&N filter. No trouble codes are displayed and it gives me a "no codes" on my OBD II scanner.
Please, give me your thoughts. Would it be advisable to drive home, about 2000 miles, or should I have it repaired asap. Also if only one injector leaks should I just replace this one and don't worry about the rest.
Thanks. Hoiman

Have your injector balance rates checked.....

Planning to have it scanned today to see what the injectors are doing. I am evaluating to see if I can drive it home to British Columbia where I have the tools and garage to work on it.
Thanks, BriteWhiteRam for your input.
Hoiman

It shouldn't hurt it too badly, but just be nice to it, check the oil periodically to make sure you're not getting oil delusion, You can probably just replace the one or more that are bad, replacing all 8 would hurt :ouch:

i would repace all them if your going to replace any it would suck to get it all together and start it and end up with a fuel knock due to new and old injectors mixed

replace all of them, i just recently did an injector job and replaced only one (was out of specs) and the truck still smokes at idle

i didnt want to hear that. lol i got one injector way out on balance rates and haze at idle. wasnt looking forward to putting that much into it just to sell it.

you can give it to me how it is, you dont have to sell it :)

nah, was hoping to get back what i paid for it, but doubt it now. lol only paid 10000 for it.

I did one on a truck and like 3 months later we were back at it again... Twice the labor for one job. It hurts but i would just do all of them.

Snowbird
 

Thanks guys for your input. #2 injector is way out of balance. 7.7 and with the second scan about 100 miles later, freeway driving with injector cleaner in tank, it was 9.2. At idle it smells like raw diesel fuel. It all seems to be the injectors on the left bank. This makes me wonder if there is more going on than just the injectors. Are there check valves in the system to keep the pressure up to the injectors? Can anybody tell me?
In any case all the injectors will be replaced. I don't want to go through this a second time by having one fail on the right side.
Thanks. Hoiman.

I'm on my 3rd set, with the current set having ~70K on them. Balance extremes: +2.5 and -2.0. If you have a TechII, check the PWM on those injectors. My +2.5 shows ~0.4 msec and my -2.0 shows ~.27 msec (worst I saw was 0.21msec). This is far below the +/- 4.0 (P) and +/- 6.0 (D). Smoke comes and goes, but does smoke bluish with increasing regularity and heavy smell. Still looking for a cause. Engine has 350K, '01 LB7.

have you looked into command pressures or anything like that ????

if your fuel pressure is low, its gonna haze all the time as well ... no injector will solve that issue ..:c:

pressures OK
 

I've got both an Edge monitor and access to a Tech II through work. Pressures are where they need to be. Changed both fuel filters and my fuel source. I run Stanadyne Performance (or, if I run out, I've got some Lucas or Power Service-silver bottle as a backup). I can try Total Power FPPF; heard it helps.

PW appears to be normal. BR on all 8 is nearly 0 +/- 0.5 after a 4 hour highway run, but a couple will drift out further after the engine cools down a bit. Sometimes I see smoke, others not so much, but the smell of unburnt fuel is in the exhaust. I can apply 1% throttle angle and defeat the auto balance program- I hear virtually no difference in the engine and if anything, the slightest loping (probably nothing to get excited about).

I'm going to try some Seafoam in a tank and see if it helps. First startup and a long run doesn't show much if any smoke. Slow driving around town and warm idle reveals more smoke. Putting off the injector swap as long as I can. Last few oil analysis samples have shown nothing in the oil (no fuel, water or coolant).

Sounds like there just having a low pop pressure issue then .. a swap is nearing unfortunatly ..:ouch:

swap
 

Perhaps. It is what it is. This time, however, I'm looking to do them myself as I can get the sprays cheaper than through a dealership. Downside: looking to buy a used beater car for transportation in the meantime (which appears to be a necessity, given the high miles on this truck). Still cheaper than a new DMax!

Trade this one in on a newer one ... thats my plan .. with my 12v truck :rocking:

New truck....
 

Already gave that one some thought. First, I'd have to opt for one that doesn't have all of the injector issues like those of the 2005+ (need to get closer to 2009 and up). Next, my dealership service mgr (who I've worked with exclusively for my service over the years) tells me that the newer used DMax trucks are expensive, usually high miles and are gone within days after they hit the lot. I've looked a 2014+ to see what I can get with my GM employee discount and it don't look pretty- close to $50K for a 2500HD w/DMax. Figure in higher insurance being a new vehicle and $500/mo (+) monthly payments. Eventually, yes I'll go new but hard to justify right now.

I've recently learned that I'm eligible for employee discounted prices on parts- I'll have to look into the cost of injectors from that source.

might be worth it to just pile in 10K and make your truck what YOU want it to be at that point .. then you will be real happy with it and no need to spend like 50 K .... unless you wanna make your truck a real monster ..:rocking: