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Discussion Starter #1
So I'll start by apologizing here for posting yet another thread on injectors, but I've been through the forum and lots of google searches and can't quite pin down what's going on.

Truck has 190k miles. I bought it at 188k at auction, so I really have no idea what the history of it was before that. This is my first diesel so I'm not sure what to expect.

The truck seemed to be well maintained. I changed all the fluids and put in all new suspension parts, steering parts, new tires, new batteries, fixed some problems with the rear differential, new wheel bearings, etc. When I drained the oil it seemed odd. It wasn't black like I'm used to with gas engines, it was nearly clear. It looked brand new to me. It also seemed to drain WAY more oil than I ended up putting back in. That should have been a clue, but I just figured maybe some idiot put in way too much oil before putting it up for auction??

It always seemed to smell, but I figured that's maybe just what diesels do? It also white smokes just a little bit at idle (you need a good black background to even notice). It gets terrible MPG (14-15mpg). I wouldn't have done anything except I was out at a waste water reclamation plant and a guy walked by and told me I had bad injectors. Told me he used to run a fleet of LB7s back in the day and identified the problem by the smell alone.

So then I started looking into things. I ran the balancing rate tests. Here's a the results


None look too terribly bad. 2.9 is the highest, but none over +/-4, which I thought was the threshold.

FYI. It starts like a dream. Literally in maybe 1 second. Faster than any gas car/truck I've ever owned.

I didn't do the return test because I figured that was usually only for hard starts. I can do that easy enough if you think it's necessary.

So, what do you think is going on? If it's injectors, why do they all seem within limits on balance rates and why does it start so easily?

Oh, one other thing, there's a stored trouble code P0181. No MIL. I just noticed it when I scanned codes. I don't think that has anything to do with this, but I figured I'd relay it here.
 

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I just changed my injectors. No symptoms except fuel in the oil that was found by Blackstone UOA. It came back @ 4% fuel. No smoke, balance rates were about 3 on two injectors the others were lower, no hard starts just fuel, in the oil. I suppose it could of been leaking return lines or leaking somewhere else but the high pressure side of my injectors were filled with garbage so no troubleshooting was done. Just changed injectors and torqued everything to spec with all new hardware.
 

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Discussion Starter #3
Thanks. I generally am OK with changing something out if I have a hunch it’s bad or close to going bad. However these injectors are going to cost me $2500 and I’m just hoping that I can get really confident that they’re the problem before I pull the trigger.
 

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$2500 plus new return lines, and an install kit with lower valve cover gaskets, cup o-rings just in case you pull a cup out, ect. my total bill for the kit was $3528 but $300 of that is core on the old injectors. But I used SAC style injectors which are a little bit more and added in new valve cover hardware (which I'm glad I did). I'm hoping the SAC will be a better investment over the VCO in the long haul. We will see. I got mine from Lincoln Diesel Specialties. They seem to have a good rep here on the Duramax forums. They answered my questions and shipped very quickly.
 

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I made a mistake saying new return line I meant new high pressure lines. You will see when you take them off why you should get new ones. There is no way to clean them out unless you have some type of equipment. Even then I dont think you could do it properly and risking your new injectors over those lines would be a bad move.
 

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Sounds like you have injector issues for sure as you are making oil and smoking at idle.

We have all the parts you need here at Lincoln Diesel Specialties to fix your truck correctly and we have great prices! Let me know if I can help.
 

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Discussion Starter #7
Thanks everyone. I'll probably end up going with LDS, just because they've got such stellar reviews here. However, anyone have any experience with injectorsdirect.com? They've got a set of new Bosch injectors with high pressure lines and all the ancillary gaskets/seals for $2599.99. Seems like everything I would need at a pretty reasonable price.
 

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Sounds just like mine the first time the injectors went south on me . The second time I switched to SAC style 45 over injectors since all the newer trucks run SAC style and have way less issues I fugured why not . I like them they run well especially with tuning . I also hear you can get SAC style in stock spec now that just swap out and run like stock . I also recommend LDS ive sent a few people there an all were happy with the outcome . GET THE WHOLE KIT LINES AND ALL ..Think about throwing in some extra filtration while your at it .
 

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I made a mistake saying new return line I meant new high pressure lines. You will see when you take them off why you should get new ones. There is no way to clean them out unless you have some type of equipment. Even then I dont think you could do it properly and risking your new injectors over those lines would be a bad move.
I agree with this 100%. I would also suggest changing the return lines. Just to be sure one of them isn't leaking as well. It would suck to have to open it back up after installing new injectors. Also make sure the injector sleeves/cups are pulled out and resealed, maybe replaced. I am running LDS 45%+ SAC injectors and think those or the stock size are the way to go. Lincoln Diesel Specialties will take care of you whatever you need!
 
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