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So my dads truck is completely stock, dpf intact, however I've noticed soot in the tailpipe. plugged cts race into it, not gonna tune it, but curious what the soot level should read, and what the dpf pressure variance should be at. Wondering if these things will help diagnose if the dpf is cracked or something? it will smoke out the tailpipe if you mash the pedal.

I've taken it to the dealer, however they didn't know anything about those and the service manager said he changed the air filter and that should get rid of the soot! haha
 

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Im Superrrrr!
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Its an oil burner man....gonna be soot even if you cant see smoke.

Even gasers get carbon buildup in the exhaust.
 

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There should be no soot in the stock tailpipe. DPF is probably cracked, dealer should replace if it's still under the emissions warranty period.

Never monitored pressure variance, but soot levels would be between 0-44G. Usually a regen would occur between 38-44G.
 

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Yeah I agree with John. There's gonna be soot bold up in just about every car
 

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when i pulled my stock exhaust out, the entire system had soot in it....Even after the DPF....its a diesel:rofl
 

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Discussion Starter #7
There should be no soot in the stock tailpipe. DPF is probably cracked, dealer should replace if it's still under the emissions warranty period.

Never monitored pressure variance, but soot levels would be between 0-44G. Usually a regen would occur between 38-44G.
thanks. that's what I was looking for. can't believe 60% of the people who responded thought that soot was normal :cookoo[1]:
 

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DPF cracked. If it smokes black somethings broken. I had this happ back in 09.
Dealers kept telling me "its normal or we found no problem." I got the around a around trying to get it replaced.
DPF = no black smoke.
 

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Do the PCV reroute and a large part of that oily sooty mess on the tailpipe and the dpf including the complete exhaust system will slowly go away to just a minimum.
I would have to think you have a dpf problem at this point.
 

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Can you define "soot"? If I run my finger around the inside of my exhaust tip, it comes back black. It's slightly more noticeable since the cat ran away.... There's a very thin layer of "soot" in there and every other diesel I've ever seen has the same exhaust deposit, Ford, Cummins, Dmax etc. If it's caked up thick in there, yeah, something's not right but I think (hope) a little unburned hydrocarbon is OK, at least in a non-DPF truck.
 

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Do the PCV reroute clean the black sooty film from the inside of your tailpipe, after a few thousand miles wipe your finger again and it will have a thin light gray film that you can wipe off with a towel.
Now if your running a big tune it would be darker.
I built my own dpf only delete pipe, deleted the muffler, the cat is still on and running the Quadzilla Stealth II set on economy nodpf tune.
The PCV reroute makes a BIG difference with having a cleaner burning exhaust all around.
 

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Soot after the dpf is not normal. Everyone who says that doesn't own a truck with a dpf.
My truck at 35k miles had zero soot. My dads lmm at 80k still has no soot.
It will allow soot to pass through if enough is there at a time (like on a fairly smokey tune) then it will pass through. If stock then it should be virtually spotless
 

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So my dads truck is completely stock, dpf intact, however I've noticed soot in the tailpipe. plugged cts race into it, not gonna tune it, but curious what the soot level should read, and what the dpf pressure variance should be at. Wondering if these things will help diagnose if the dpf is cracked or something? it will smoke out the tailpipe if you mash the pedal.

I've taken it to the dealer, however they didn't know anything about those and the service manager said he changed the air filter and that should get rid of the soot! haha
I have been having this exact problem. The dealerships I've been to only scan for codes and can't find anything.

Mine hazes pretty bad at idle while in regen, and also smokes heavily while accelerating in regen.
 

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What is a dpf? Does an 05 lly have one? My father in laws has a major soot problem and smokes like a chimney.
 

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?

Soot after the dpf is not normal. Everyone who says that doesn't own a truck with a dpf.
My truck at 35k miles had zero soot. My dads lmm at 80k still has no soot.
It will allow soot to pass through if enough is there at a time (like on a fairly smokey tune) then it will pass through. If stock then it should be virtually spotless
so the person above with an lmm

wouldent know ?
 

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What is a dpf? Does an 05 lly have one? My father in laws has a major soot problem and smokes like a chimney.
Basically its an exhaust filter only 07.5 and older have it, thanks to epa.
 

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My factory tail pipe had 96000 miles on it when I did the dpf delete and it was clean no soot. My friends where amazed how clean the tail pipe always was being a diesel. I would say soot means the dpf is screwed up.

Sent from my Autoguide iPhone app
 

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did you mean older or newer

Basically its an exhaust filter only 07.5 and older have it, thanks to epa.
I assume you mean 7.5 and newer . . . never seen them deleting emission controls on newer models, unless there is some wholly new technology to take its place.

Is the setup the same on medium-duty or is there some kind of weight cut-off for this treatment.

Saw the difference in exhaust, or more to point saw the mess around the EGR on a Ford Turbo a friend of mine broke down for bad heads and I would think an EGR delete is in order for my 06 LBZ once the warranty ends in a year. Is that the same as the PCV delete being touted?

Brian

BTW what does DPF stand for Diesel Particulate Filter? or . . .
 
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