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Discussion Starter · #1 · (Edited)
My 2003 Duramax LB7 with 137K started having Black Smoke in Idle. My Local GM Service Manager suggested trying different Injector Cleaners, one of which was 2 Quarts
of ATF in a Full Tank of Fuel. I've tried Diesel Supplement, Seafoam, Marvel Mystery Oil, and I tried one Quart (1% ATF in 25.xx Gallons) for a Tank of Diesel. Now, I've
filled up at Lowes in Kingman, AZ and the remaining ATF should be about .32% in a full tank. I'm down to about 1/2 tank now and I still have Light Blue Smoke in Idle
each and every time I am at a stop light. But at least I don't have the dark black slobbering rich Diesel droplets coming out of the Tail Pipe. I'm beginning to get concerned
about my Injector Status. The Truck starts good, Idles good, Runs Good, drives good with plenty of Power for the AZ 6% Grades.

I've used Torque Pro to get some screen captures of the Balance rates in Park, with Foot off Brake, at 175 Engine Temperature, and with Truck in Drive, with Foot on Brake,
and nothing else being turned on.

Photo's are attached with the Cylinder Balance rates and Fuel Injection Rate according to the data Torque Pro gathers. The Idle Fuel Injection rate of 83.xx CC/MIN looks incorrect to me. It appears to be 10K to large if the actual Fuel Injection rate at Idle is the 8 to 9 mm3/min that some forum postings state.

Will some of you Diesel Guru's look at the attached Photo's, and make your best guess of my Injector status from the Data. My Local (Missouri) GM Service Manager says
I need all 8 Injectors. But, I'm currently 1600 Miles away from their location.

I need a bit of help determining what I should do, if anything, because of the Balance Rates in my Stock 2WD Duramax Ext Cab w/Allison.

ELM327 Ver 1.5 Firmware and Torque Pro were used to get the Data on the Balance Rates, with the Torque Custom PID's.


Larry
 

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Discussion Starter · #3 · (Edited)
Ordered Injectors & Lines from LDS and they are now installed. My mechanic showed me
three Injectors that have the O-Ring malformed from being installed incorrectly by GM,
and this allowed my engine to burn the oil, making the Blue Smoke.

I've attached a couple of Photo's of two of the three Injectors. Three out of eight installed
with malformed O-Rings is 37.5% which isn't a good success rate. Now I'm wondering how
long my Injectors would gone with good O-Rings? The pictures don't really show the side of
the O-Ring being pulled up towards the top of the Injector.

Has anyone else seen the same type of malformed O-Rings on their Injectors?


Larry
 

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The orings on the outside of the injectors only keep oil from getting down in the injector cup and I don't think would have anything to do with the injector failure
 

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Discussion Starter · #5 ·
Yes, you are correct! But, while standing and looking at a Duramax puffing Blue Smoke out the
exhaust, still means all 8 of the Injectors have to be removed to see which one(s) are allowing
the Oil to bypass. At that point it would be a crazy decision to reinstall them with new O-Rings
at ~140K miles.

I guess I should have let it puff the Blue Smoke, and did some Free Advertising!

Larry
 
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