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Discussion Starter #1 (Edited)
05 LLY, 55K miles.

I usually run Level 2 PPE, but put it back to stock to try and diagnosis this.

Last two days, the truck is running progressively worse. I thought it was running a bit rough, but now it is really bad. It smoke screens everywhere, and is hardly drivable.

First thing I did was the fuel filter, which yielded no positive results.

It blows whitish/gray smoke when you are on the throttle at all. It might be a bit blue. I believe diesel is making its way into the oil, as it is a bit high. The exhaust smells like diesel.

It was clattering bad at around 1500-1800 rpm, but now it is always clattering and smoking all the time. It is generally running really rough and is lower on power.

Fuel mileage is terrible over the 1/4 tank used since this started. Must be under 10 mpg.

I did the ice pick trick, to no avail. Still runs like crap. PPE has an injector balance reading on it, all are around 7 ms, but from reading on here, that is in reality pulse width which doesn't mean anything.

So, I assume I have a bad injector. How do I determine which one it is? Or does anyone have any other advice? Again, this truck only has 55K on it.

Also, there aren't any codes being thrown. At this point, I can't drive it as it smokes so badly and clatters like it is going to blow up.
 

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injectors dude
 

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Check the boost tubes and boots. Could have a hole or even one off.

Have you checked the FICM harness at the side of the alternator-??

Cut the zip tie and inspect the wries very good.

How is the air cleaner-? Have you cleaned the MAF sensor-?

Drop a little engine oil on a white paper towel-- the oil will stay in the center and the diesel, if any, will make a halo around the oil spot. That usually shows diesel ion the oil. You should not condemn the injectors just from a simple test-- have someone read the injector balance with a TechII.

It is rare for the injectors to go bad on a low mileage LLY Duramax-- unless the fuel is contaminated.

Many engine problems will throw a code, but not always -- so keep checking for codes and post them.
 

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I would first start to check the EGR, if you suspect its an injector, do not run the truck. The injector could be sticking open, and you can/will melt your piston and have major damage. What side of the motor does the knocking come from?

You cant check the balance rates on the PPE's IIRC, but I would tow the truck to the dealer or some place that can run a balance rate test on your truck and see exactly (if any) injectors are out of spec.



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Discussion Starter #5
Check the boost tubes and boots. Could have a hole or even one off.

Have you checked the FICM harness at the side of the alternator-??

Cut the zip tie and inspect the wries very good.

How is the air cleaner-? Have you cleaned the MAF sensor-?

Drop a little engine oil on a white paper towel-- the oil will stay in the center and the diesel, if any, will make a halo around the oil spot. That usually shows diesel ion the oil. You should not condemn the injectors just from a simple test-- have someone read the injector balance with a TechII.

It is rare for the injectors to go bad on a low mileage LLY Duramax-- unless the fuel is contaminated.

Many engine problems will throw a code, but not always -- so keep checking for codes and post them.
I would first start to check the EGR, if you suspect its an injector, do not run the truck. The injector could be sticking open, and you can/will melt your piston and have major damage. What side of the motor does the knocking come from?

You cant check the balance rates on the PPE's IIRC, but I would tow the truck to the dealer or some place that can run a balance rate test on your truck and see exactly (if any) injectors are out of spec.

The bundle of wires by the alternator look fine. As do the boost tubes.

I haven't checked the air filter nor the MAF. There is a pressure relief type gizmo on the air box that I noticed was red, until I pushed the relief button. What is that thing?

Oil smells like diesel to me, and is definetly high. The drop test didn't really show anything.

Haven't checked the EGR, I am going to buy the block off and check it out. For now its getting dark, so it looks like im drivin something else this week.

This problem gradually occurred, it wasn't something that suddenly showed up. Progressively it has gotten much worse. I think the clatter is coming from the drivers side, but it is tough to tell. I'll probably have to get it towed somewhere. Sucks.
 

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The sensor on the air cleaner is a flow sensor.

The turbo pulls a lot of air during heavy use and can build vacuum, if the air filter is restricted-- that vacuum will pull the sensor from green to red and lock there. That tells you there is a problem. If the filter was clogged before and you had the filter changed-- they may not have reset it. But they have not changed it-- or--- SOMEONE MAY HAVE LEFT A RAG IN THE TUBE AND CAUSING THE FLOW PROBLEM.

Check the air filter very carefully.
 

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Discussion Starter #7
Nobody works on it but me, keep in mind.

Ok. I just checked the air filter. It is a bit dirty, but not bad. The air sensor gizmo has been fine since I reset it.

Another note. It doesn't really smoke at idle. It doesn't start to smoke until you put it in drive, or get the rpms up a bit. And at that point, it is a smoke screen. Idle is ok. It is a bit rough running, but no smoke really.
 

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Discussion Starter #9
Question.

Can someone with EFI live plug into my truck, to check my balance rates, without me having a license for EFI live? I don't want a EFI tune, I just want the diagnostic capabilities. Someone I know has EFI so I am hoping that I can do this.
 

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subscribed.......
 

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Question.

Can someone with EFI live plug into my truck, to check my balance rates, without me having a license for EFI live? I don't want a EFI tune, I just want the diagnostic capabilities. Someone I know has EFI so I am hoping that I can do this.
You don't need a license to scan:thumb
 

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Where are you located
 

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Discussion Starter #16
Balance rates are around 4 on two cylinders. The main and pilot are tapped out on the efi live gauge. Cylinders 3 and 6 read high. 3's and around 4 respectively. Fuel pressure is fine. 100 cmm on the main at idle. 4 ccm pilot.

Any advice?
 

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Like skinnyR1 said, cylinders 3 and 6 were varied between 3.5 and 4 when in park. All other rates were right around +/-1. Balance rates seemed to actually get closer to 0 when in drive with the brake on. Truck smoked real bad when we first started it, but seemed to clear up some after a little while. When we drove it around the block it started smoking real bad, greyish smoke. Any ideas on why the main injection would be reading around 100mm^3 at idle? at 1200 rpm it pretty much pegged the gauge at 120mm3 on the scan tool.
 

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Dealt with a very similar problem last night. The truck had the EGR valve stuck open. Thought for sure we had a fuel problem. I'd try a block off or pull it out and clean the carbon off of it.
 

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If I was to say what I thought it would be. I think your got a bad batch of fuel and ruined some injectors. Although, you do want to start with the cheaper fixes.

Could you post a video of what the truck is doing?
 
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