06 Duramax lost some power, gained a lot of black smoke
 

Any thoughts? EGR maybe? Do the catalytlic converters clog? Truck has 95,000 miles. Fresh air and fuel filters. Seems to start and run fine but under load it blows black smoke and I have to put my foot in it a lot farther lately. No error codes...

think you got a bad batch of fuel and plugged the filter again? Maybe a MAF sensor? should have thrown a code for that tho. Are u running the stock filter setup?

Thanks for the reply. After I started noticing the power loss and seeing the excessive smoke I decided I was pretty close to needing a new fuel filter anyway so I changed it and it didnt seem to fix it. Everything is stock except for a K&N air filter element. I've run a couple tanks of fuel through it and tried some injector cleaner and it's is the same.

Is that an oiled filter I take it? Have tried cleaning the MAF with some cleaner from Napa or similar?

Yeah, it is an oiled filter. I'll try cleaning the MAF sensor. That's a good idea, thanks.

imo, you should go back to the stock or paper style filter, it is said to support near 500hp so unless you are putting down some big hp #s, it just not worth the trouble of having to keep cleaning the maf sensor.

Get rid of the k&n filter.. We did a dyno test of 5 intakes and filters on our 06 shop truck and the k&n actually built the least amount of power. But i would try cleaning the maf sensor since the k&n have a nasty habit of gunking those kinda thing up. And if you want a aftermarket filter i would look into a afe intake or a sb.

Scott is right the K&N oiled air filters are not good. They plug up the MAP sensor and can get into the turbo and could hurt the turbo. :c:

Thanks for the info guys. I'm going to try cleaning the MAF tonight and if that's the problem I'll be yanking out the K&N and look into some of the options you guys mentioned.

06 duramax/ same problem
 

I hope I'm doing this right... I have an 06 Duramax as well. Last night on the interstate I noticed I was losing some power. When I looked in my mirrors I could see smoke in the lights of the cars behind me. So today after reading several blogs I had the K&N filter recharged, and got some MAF cleaner from the auto parts store down the road. But engine light is still on and still have excessive smoke when accellerating?

Yeah, cleaning the MAF sensor didn't help mine either. Other thoughts?

Are you running any tunes? Your not getting enough air? If cleaning the MAP sensor and the air filter does not change things, let us know?

I went ahead and made an appointment for monday morning, just bought the truck 3 weeks ago. There were two other codes on it other than the MAF codes so if I learn anything on Monday I will fill you in. I thought for sure it was the K&N clogging the MAF... Sorry

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D. racer, You said you had no codes. Just out of curiosity... Who checked it for you? The reason I ask is I took mine to the auto parts store where they checked it with a tiny handheld and came up with nothing. So I went to a shop next door where they had a much more elaborate set up and found four codes as follows:

P2610 Control Module Igntion Off Timer Performance

P0101 Mass air flow sensor performance

P102 Mass air flow sensor circuit low voltage

P0540 Intake heater feed back circuit

I cleaned the MAF last night and got a little better, I'm going to get it rechecked and see if the MAF code is still there.

Checked the codes with a handheld reader so maybe I need to have the shop check for codes. What ended up being the solution on your truck?

what about excessive carbon buildup from egr or vanes in turbo not moving fully

Maybe... Are you thinking excessive carbon buildup could be clogging the catalytic converter or????

with 95k i doubt it unless the guy before you was running some really smoky tunes. i know the egr on my truck with 140k was almost blocking the intake ports fully before i cleaned it but i got a totally different engine

with the EGR on these engines they intakes (bolted to the heads) can fill with a thick black oily/sooty build up, that could be killing your airflow and causing the smoke and reduced power

To the other guy with the codes, have you tried replacing the MAF sensor?

No Idea
 

I have no idea? I guess it was the MAF. I put in some fuel catalyst, filled the tank and just putted around town on a bunch of short trips, nothing over 30. By Sunday night I really had to try to get it to smoke. Brought it in Monday and they cleared the codes and re set the check engine light. Charged me $100 and said it was the MAF? Put 2000 miles on it this week and seems to be doing just fine...

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I was going to just replace it but it was a factory direct order that would have taken 3 days to get and it was not a $10 part. I think it was around $200 with the core, so I opted to just let the dealer look at it first before I started replacing stuff. Thanks for the input everyone, you have all been more than helpful. Looking forward to my next panic when something goes wrong...

Is removing and cleaning the EGR relatively easy?

you got to buy a kit to get rid of it and to keep it from setting a code. no idea on how easy it is.

Other than one bolt that is burried (open end wrench and long strong fingers will get it), it's straight forward to take out and sepperate the solenoid from the valve itself. If you take the solenoid off you can push the valve in and out to clean everything including the solenoid, BUT that's not to say the solenoid itself isn't sticking internally. It's worth a few hours in the garage to try though. It would only cost you some cleaner, but it would probably be better if you just replace it.

I have an 04.5 LLY and I switched to the 06 LBZ air intake, had the computer reflashed, I was running the stock AC DELCO air filter in it and I would blow black smoke like I had a huge tune in it, I tried putting a WIX filter in it, it did the same thing, after about a week, I was seriously down on power, my filter life thing on the intake was at 80% with a new filter. I would flip the filter around and it would run fine for about 50 miles, egts would go way up smoke would come back and I was back down on power but still no check engine light. I put a K&N filter in it (I hate K&Ns) and it ran like a bat out of hell. I don't have any tunes in the computer never have, but I think I was sucking the filter closed.

that sounds pretty fishy

K&N filters can be the cause of MAF sensor malfunctions due to oil contaminating the sensor

That may be true sometimes, but my truck has had an oiled K&N filter for almost 100,000 miles with no problems :tu:

wow, 5 year old thread. digging up the grave are you?

My diesel instructor told me a story that when you get too much fuel into a cylinder it will discharge the excess carbon on the exhaust stroke. Maybe you are getting too much fuel.

Is this for reals?:pca1:

You know now that I look back at this thread it honestly sounds like a boost leak... hmmm how times have changed:argh: