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Discussion Starter #1
I have a 2011 LML 134000 miles it has a PPEI 5stage tuner and is deleted. The truck has been great until I too it to our cabin. Coming home there is a few steep down grades and both time when I got to the bottom the truck started stumbling and puffing white smoke it took about 5 min running it to get it to clear out. I had to step on the throttle and raise the rpms up to 2500 before it cleared. I’m new to diesels so any advice would be great!
 

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White smoke is coolant. Check your coolant level and also take the truck for a 15 minute hard run and see if the upper radiator hose is rock hard. If so it is head gasket time.
 

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When checking the upper rad hose you want to get it up to temp be hard on it then let it sit for at least 5+ hours. If it's hard after that your keeping pressure in the system and 98% of the time headgaskets . If you take the degas cap off it shouldnt have any pressure left in it either. Can try replacing it before headgaskets as its 12 dollars compared to 1k to 4500
 

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Discussion Starter #5
Well took it for a hard ride and the hose is pretty darn hard. I’ll see in 5 hrs what it’s like.
 

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Hows it deleted? Full exhaust? Egr deleted also or just unplugged? Stock down pipe with 9th injector still installed? Pull intake and mouth piece is there oil inside?
 

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Well after a few hrs the hose was soft no pressure so idk what’s going on
GOOD News, not head gaskets!

Is your coolant level dropping or staying the same, check it several mornings in a row when it is cold to see what it is doing. If necessary use a marker to mark the level the first time.

If it is dropping you are losing coolant somewhere and the white smoke tends to indicate it is going into the cylinders. A coolant leak in the EGR Cooler (IF it is still there) or the Turbo both can put coolant into the engine.
 

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Discussion Starter #9
Ok so took it to shop and this is where I’m at. my truck has the egr turned off from the ppie tuner. There is no block off plate. What they think is the egr is opening while I’m costing down a long hill and causing the Engine to run rich. I’m getting a scanner so I can check the mass air flow sensor while I’m doing the same down hill run. They say if the numbers are low that’s probably what’s going on. They we’re not able to open the EGR because of the tune that’s on the truck so they could not replicate the problem . I should have the scanner by end of the week so I’ll update ASAP. Thanks
 

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Personally I've never seen or heard of an lml blowing the egr open under load since they've been deleted n tuned in 2013 but theres a first for everything.
 

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Discussion Starter #11
At the shop they noticed the egr was still plugged in so they disconnected it. Now my truck is coming up on boost a lot faster and really feels smoother. I don’t know if the tune was causing the egr to stay open or what. Once I get the scanner I’ll know more but for now I’m happy.
 

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Discussion Starter #12
The truck has a full exhaust and the delete is done through the PPEI tune it has stock down pipe still. I’m thinking I need to replace the down pipe soon so it don’t blow up on me.
 

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Discussion Starter #13
Thanks for everyone’s thoughts and input I just joined this forum and have had a lot people trying to help...I think I’ll stick around and hopefully be able to help someone in the future!
 

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You can run stock down pipe without issues I've got a few running around like that and theres plants of others I'm sure. Your egr still being plugged in could have affected things.
 

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My truck has almost 180,000mi and been deleted since 100,000mi. I still run the factory down pipe with no issues. All changing out the down pipe does is change the sound of the exhaust and remove the port for the 9th injector. You will be fine to leave the factory down pipe if you wish too. And the issues you were having, I would say, was definitely from the EGR still being plugged in. I followed the old H&S instructions when deleting my truck and it clearly says to unplug it. When deleting my dads truck with PPEI, I asked them and they said to follow the H&S instructions too.
 

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:thumb ^^^^
There’s 2 positives when going with a aftermarket downpipe.
You’ll have something to do for about one day removing the stock DP installing the aftermarket downpioe.
Your wallet will be much lighter not having to lug around that extra weight money you spent on the DP.
Only if your having exhaust leaks from your stock downpipe, leave it on.

Yes, leaving the egr plugged in with even tuners saying it’s ok could lead to issues.
I had the same problems, luckily my original Edge Insight I monitored EGR command.
I noticed it was jumping up and down from 0% - 100% running rough, I unplugged it, this solved the problem.

Below is for the LMM, stock is oval shaped about 2 3/4” x 3 1/4” where the aftermarket is 3”, I had absolutely no gains.
 

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Discussion Starter #17
I contacted PPEI and they said the same thing. I think it was unplugged but the shop that I bought the truck from probably seen it unplugged and figured it should be plugged in. Hopefully I’ll run up to the cabin this weekend and see. I thought this truck was amazing before now it running noticeable better and just blows my mind how much power it has! Thanks again for all the info.
 
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