Does thick white smoke out the exhaust mean turbo failure?
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From: Northern VA
2010 GL350 BLUETEC, 2013 E350 Sport
Does thick white smoke out the exhaust mean turbo failure?
Our GL started smoking real bad the other day. So bad that cars behind had to back off like since visibility anywhere closer than a 1000 feet was 0.
I thought it it was likely the turbo, but don’t want to waste time or money trying to rebuild the turbo if there are other likely culprits. Btw, driving it home: no new CEL and difference in driving character. Basically except for the white cloud fogging the entire neighborhood, you would not have thought there was a problem from how it drove.
I thought it it was likely the turbo, but don’t want to waste time or money trying to rebuild the turbo if there are other likely culprits. Btw, driving it home: no new CEL and difference in driving character. Basically except for the white cloud fogging the entire neighborhood, you would not have thought there was a problem from how it drove.
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2009 GL 320
Usually white smoke is head gasket. I would check your coolant level and see if it is low or non existent. Also check oil fill cap and see if the oil is milky (mixed with coolant). Post pics if you can.
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From: Allentown, PA
'08 GL 320 CDI
Agree. For one, you said didn't notice any difference in driving performance - if the turbo was kaput, you would have diminished power. Two, if a turbo is not working properly, you would get black smoke as not all the fuel would be burnt. Another thing you can check is to look for bubbles in the coolant reservoir.
EDIT: Meant to say if a turbo is NOT working properly. Forgot the word "not"...
EDIT: Meant to say if a turbo is NOT working properly. Forgot the word "not"...
Last edited by DennisG01; Nov 26, 2020 at 11:35 AM.
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NGL450 w/EORP, S550
Is this a GL350?
Headgasket is a possibility
Turbo is too, but less likely - an oil seal has failed and oil is being burned in the turbo.
Coolant burns like a white fog, oil burns a light gray haze.
either of these two will kill your engine in short order, not to mention all the expensive downstream stuff like catalytic converters, o2 sensors etc...
park it and diagnose,
Headgasket is a possibility
Turbo is too, but less likely - an oil seal has failed and oil is being burned in the turbo.
Coolant burns like a white fog, oil burns a light gray haze.
either of these two will kill your engine in short order, not to mention all the expensive downstream stuff like catalytic converters, o2 sensors etc...
park it and diagnose,
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From: Emmett, ID, USA
2007 GL450
Oil leaking into the exhaust. A lot of it.
If it were coolant, the fog would dissipate rapidly. Oil makes a dense white smoke when vaporized by heat. This is how sky writing works: Oil is sprayed into the exhaust. Certain tanks do the same thing when they have an urgent short term need to obscure their movement.
If it were coolant, the fog would dissipate rapidly. Oil makes a dense white smoke when vaporized by heat. This is how sky writing works: Oil is sprayed into the exhaust. Certain tanks do the same thing when they have an urgent short term need to obscure their movement.
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From: Northern VA
2010 GL350 BLUETEC, 2013 E350 Sport
Coolant level was a little low, but not dramatically.
Oil was not milky but 4 qt low
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2010 GL350 BLUETEC, 2013 E350 Sport
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Thread Starter
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From: Northern VA
2010 GL350 BLUETEC, 2013 E350 Sport
considering I had to add 4 qts to get back to normal range, I’m inclined to believe your suggestion of oil seal having failed. Is there a common seal that is the prime suspect?
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From: Northern VA
2010 GL350 BLUETEC, 2013 E350 Sport
I think you’re right. After adding 4 qts oil to bring it back to normal range, I let it idle until it was warmed up. There was no smoke at all at idle and no milky oil or bubbles in the coolant reservoir. The fog bank begins when the truck is under load (turbo spinning)
Last edited by S-Vibes; Nov 26, 2020 at 10:13 PM.
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NGL450 w/EORP, S550
Thanks for taking the time to help:
I think you’re right. After adding 4 qts oil to bring it back to normal range, I let it idle until it was warmed up. There was no smoke at all at idle and no milky oil or bubbles in the coolant reservoir. The fog bank begins when the truck is under load (turbo spinning)
I think you’re right. After adding 4 qts oil to bring it back to normal range, I let it idle until it was warmed up. There was no smoke at all at idle and no milky oil or bubbles in the coolant reservoir. The fog bank begins when the truck is under load (turbo spinning)
overhaul or replace turbo and get back to us.
sounds like your headgasket is ok given that you have no crossmojination of oil and coolant in either reservoir. The comprehensive true test of that is a chemical test that looks for combustion gases in the coolant - a test kit can be had for less than $100 on Amazon (and last you years).
Last edited by Max Blast; Nov 27, 2020 at 02:07 AM.
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From: Emmett, ID, USA
2007 GL450
Thanks for taking the time to help:
I think you’re right. After adding 4 qts oil to bring it back to normal range, I let it idle until it was warmed up. There was no smoke at all at idle and no milky oil or bubbles in the coolant reservoir. The fog bank begins when the truck is under load (turbo spinning)
I think you’re right. After adding 4 qts oil to bring it back to normal range, I let it idle until it was warmed up. There was no smoke at all at idle and no milky oil or bubbles in the coolant reservoir. The fog bank begins when the truck is under load (turbo spinning)
Sorry, tough break.
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From: Northern VA
2010 GL350 BLUETEC, 2013 E350 Sport
then oil it is - your turbo is oil lubricated and probably water cooled. Oil is getting past some seal and into the hot side of the turbo where it’s vaporized. If you weren’t 4qts low before the smoking began then your turbo is toast.
overhaul or replace turbo and get back to us.
sounds like your headgasket is ok given that you have no crossmojination of oil and coolant in either reservoir.
overhaul or replace turbo and get back to us.
sounds like your headgasket is ok given that you have no crossmojination of oil and coolant in either reservoir.
Does anyone think a bad pvc/ccv could let that much oil by? I doubt it and already ordered parts to rebuild the turbo, but I had to ask.
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From: Emmett, ID, USA
2007 GL450
You are looking at a large quantity of liquid oil disappearing. Plus, if that liquid oil were to enter the intake, you would have large increases in engine power - this is what happens with "runaway diesels": They start burning engine oil, usually through failed piston rings, and cannot be stopped because there is no throttle to shut off.
There is a similar problem with diesel equipment working around oil field gas. The engine sucks in flammable gas, and all you can do is jump off the driver's seat and run. Seems odd they don't build in some sort of backup intake shutoff system, but I guess this phenomenon is fairly rare.
Seems likely it's the oil seals on the exhaust side of the turbine..
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From: Allentown, PA
'08 GL 320 CDI
The PCV on the diesel (EGR or whatever you want to call it) does let more combustion gasses back into the intake when it fails (the rubber flap/seal inside it gets brittle). However, it's not going to anywhere near enough to cause the issue you have. I should mention, I'm assuming your EGR valve is the same as mine. When these fail, they do cause the intake runners to clog up even faster, though. For what it's worth, I eliminated my EGR system and instead plumbed it to a vapor collection canister - so no combustion gasses go back into the runners.
GL to ya OP!
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From: Northern VA
2010 GL350 BLUETEC, 2013 E350 Sport
me too. So many gurus willing to help. Thanks, ordered a turbo cartridge and will swap it in. I’ll let you all know how it works out. This is the third time I’ve had to take my turbo off, so I’m not sweating it. I prefer to just take of the heat shroud and the wiper assembly and the plastic right below the windshield. Simpler that way to get the turbo in and out.
