Smoke signals

[john.r.f]

Two days, 42 views and no help? Maybe I confused the issue with too many questions. Basically, I'd like to know if anyone else has had white smoke and difficulty diagnosing the problem?

[JohnC]

OK, I'm not an expert here, but....

If you are getting fuel in the crank case consistently, I think you need injectors.

What are the return rates for the injectors?

Does the cooling system still have pressure after sitting for 6-8 hours?

[Mark Rinker]

Yes, unfortunately there are (too) many LB7 owners here that have had multiple sets of injectors replaced, all within the 200K/7yr period.

GM has been tightening up their 'goodwill' extensions on injector warranty. You need to push to get this done - sooner than later - siting

1. the unacceptably short lifespan of the first replacement set;
2. ...the $1100 already spent on your dealer throwing parts at the problem, to no avail;

Sure sounds like you have a couple sprays hanging up. Sorry to hear that, but its not that uncommon with the LB7s. The smoke and fuel dilution are classic signs. I would ignore the compression variances, unless you are experiencing low power, rough idle, or unacceptable oil consumption.

Don't take no for an answer! Ask that your request be elevated to GM's Customer Service. Get your timeline and your receipts in order, and documented thoroughly.

Remember: Even paying half of the next 8, would be better than receiving nothing. Right now, GM is not contractually obligated to replace them, since your warranty term has clearly expired.

[john.r.f]

Yes, unfortunately there are (too) many LB7 owners here that have had multiple sets of injectors replaced, all within the 200K/7yr period.

GM has been tightening up their 'goodwill' extensions on injector warranty. You need to push to get this done - sooner than later - siting

1. the unacceptably short lifespan of the first replacement set;
2. ...the $1100 already spent on your dealer throwing parts at the problem, to no avail;

Sure sounds like you have a couple sprays hanging up. Sorry to hear that, but its not that uncommon with the LB7s. The smoke and fuel dilution are classic signs. I would ignore the compression variances, unless you are experiencing low power, rough idle, or unacceptable oil consumption.

Don't take no for an answer! Ask that your request be elevated to GM's Customer Service. Get your timeline and your receipts in order, and documented thoroughly.

Remember: Even paying half of the next 8, would be better than receiving nothing. Right now, GM is not contractually obligated to replace them, since your warranty term has clearly expired.

Good advice, Mark. I was hoping for something like that from GM. A couple of days ago I called GM Customer Service on the advice from the dealer, presuming the dealership would support some sort of relief from GM. GM called the dealer while I was on the line and spoke with one of the "writers" [a service person who is a kind of an apprentice] who told GM that the engine needed to be broken down or replaced! I was livid!

I'm meeting with the service manager today and am hoping for a three-way deal: new injectors 1/3 paid by me, 1/3 by GM, and 1/3 by the dealer. We'll see...

Thanks,

[Mark Rinker]

Good luck...and I mean that sincerely. It sucks to feel over the barrel about a product you like, with a company you support, and get the feeling that they won't / can't reciprocate.

There are lots of independents doing LB7 injector replacement these days - if you are outside warranty you might consider a good independent diesel repair shop to do the work, if GM refuses.

[silverback]

I feel your pain and really wonder now if it is worth hanging on to my 04 LB7. I was just rejected by GM on my first injector warranty replacement attempt (94K miles). Don't feel that Freeway Chevy in Chandler AZ really backed me up either. It is smoking like crazy but I have no other symptoms. Great fuel milage and power. The long term prospects don't look good if the initial replacement doesn't actaully fix the design flaw. If I could just get the first one done...

[Mark Rinker]

My 2002 K2500 (LB7) had its first set done at ~160K miles, and then it started smoking again at idle around ~270K. Neither time did it 'make oil', so I decided to continue to treat the symptom with an old farmer remedy - addin ATF to the fuel.

I added 1 quart of the cheapest no-name brand ATF I could find, usually every 2nd or 3rd fill-up, or when the smoking was bad, I'd add one quart every tankful until the smoking subsided. Sold that truck with a snowplow on it (...with disclosure of the smoking condition) at ~290K and it was still running well, delivering good mileage, and smoking a little when it idled.

Don't know why the ATF had the effect that it did, but it did - and the truck never developed a fuel knock or oil dilution problem. I think it just had eroded tips, not a full blown injector housing failure. Obviously it wasn't dumping too much raw fuel or I would have burned it down in 20K miles!

http://www.thedieselpageforums.com/t...ad.php?t=32737

Decided the best remedy was no remedy at all - and to never slow down or sit still long enough to let a little smoke bother me!

[john.r.f]

I feel your pain and really wonder now if it is worth hanging on to my 04 LB7. I was just rejected by GM on my first injector warranty replacement attempt (94K miles). Don't feel that Freeway Chevy in Chandler AZ really backed me up either. It is smoking like crazy but I have no other symptoms. Great fuel milage and power. The long term prospects don't look good if the initial replacement doesn't actaully fix the design flaw. If I could just get the first one done...

Apparently GM is seriously drawing back on their warranty service, especially on the "extended" warranties. In the past they've been very generous and maybe that's part of the reason they got into financial trouble.

Back in '06 my injectors were failing one at a time. I had one replaced in North Carolina under warranty. Back in AZ another one failed. I tried to get the Chev dealer in Cottonwood, AZ to replace them all. No way. So I went to another dealer, Steve Coury in Camp Verde, who agreed to replace the remaining 7. No way that would happen today. I'm keeping my fingers crossed that GM will agree to a partial deal even though my injectors are only borderline -even though the exhaust is smoking like a green wood fire.

[john.r.f]

Good luck...and I mean that sincerely. It sucks to feel over the barrel about a product you like, with a company you support, and get the feeling that they won't / can't reciprocate.

There are lots of independents doing LB7 injector replacement these days - if you are outside warranty you might consider a good independent diesel repair shop to do the work, if GM refuses.

Met with the dealer's service manager today for an hour and had a good, open and honest discussion. He will contact the district GM service manager and plead my case for some relief. I suggested a three-way split of the cost for replacing all 8 injectors and he seemed okay with that. We'll see.

[john.r.f]

OK, I'm not an expert here, but....

If you are getting fuel in the crank case consistently, I think you need injectors.

<<I can't smell any diesel on the dipstick, but my nose is not very sensitive.>>

What are the return rates for the injectors?

<<These were quoted to me, but I don't remember. I'm meeting with the dealer today and will ask.>>

Does the cooling system still have pressure after sitting for 6-8 hours?

<<I don't think so...but will check. I did perform the squeeze-the-radiator-hose test and it does remain flexible with the engine running. As I remember this tests whether the engine compression is getting into the cooling system via a blown head gasket... ?>>

Thanks for the advice.