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Jessapio 09-08-2019 01:52 PM

Help smoking after down grade
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!

Gatordog 09-09-2019 04:11 AM

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.

SilverGorillaLML 09-09-2019 05:59 AM

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

Jessapio 09-09-2019 01:49 PM

I will check that tonight. I hope it’s not a head gasket!

Jessapio 09-09-2019 04:44 PM

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

Jessapio 09-09-2019 09:21 PM

Well after a few hrs the hose was soft no pressure so idk what’s going on

SilverGorillaLML 09-09-2019 11:22 PM

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?

407driver 09-10-2019 06:52 AM


Originally Posted by Jessapio (Post 12203449)
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.

Jessapio 09-10-2019 11:09 AM

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

SilverGorillaLML 09-10-2019 12:30 PM

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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