Steven Solomon

Hello everyone. Newb to this forum, but have 40 years' experience working on everything from my '68 Camaro to modern Italian exotics. Wife bought a GLK350 new in 2010 and I've been following the recommended service schedules while doing a lot of the small stuff myself (oil and filter changes, air filter changes, etc.). Car now has 230,000 miles and was running like a swiss watch. For whatever reason she took the car to Valvoline yesterday for an oil change before a NY-Cape Cod trip tomorrow. On way home she called me-massive clouds of black smoke enveloping the car every time she stopped at a light. I had her bring the car to my house, opened the hood and there was oil everywhere. Pooled in every plastic crevice, coating underside of hood, etc. Pulled dipstick after waiting 30 minutes and oil level was way beyond maximum, about 2-2.5 inches up the wire. So I vacuumed out 4 quarts until the level was finally between medium and max when cold. Then I drove it. Black smoke continuing out the exhausts in such quantity that it enveloped the car. Plus car would lose power every 15-20 seconds, then get power back. Took it back home, called Valvoline (I took pics and video of dipstick and me pumping out 4 quarts and smoke pouring out of exhaust). Initial thought was that highly increased pressure could have blown head gasket, but no water or coolant in exhaust, no antifreeze in oil and no water in oil. I should mention that I removed the 2 cold air intake hoses that morning because they were falling apart, and was waiting for Mercedes to ship me new ones. OT- Do not buy "Bapmic" replacement hoses. They lasted 1 day before the glue failed and the spiral wound felt began unravelling. So there were no cold air intake hoses on the car when she went to Valvoline. I suspect that the high oil pressure spewed excess oil all over the engine compartment, and some of it was sucked into the air intakes and saturated the air filters. I let it sit overnight, drove it about an hour today with Valvoline local shop manager with me, and saw no smoke today. On parking afterwards a small amount of oil smoke when I revved to 5,000 RPM, but nothing like yesterday. I now have replacement cold air intake hoses but am worried that the air filters may be saturated with oil and it may not be a great idea to take this car on a 300 mile road trip tomorrow. On the other hand, if it is just a bit of residual oil burning off it should be fine. I have no replacement air filters so even if I pull these out and they are oil-soaked I'd have to wait until tomorrow to get new filters for the car. Any opinions on causes and effects along with opinions on whether the car is safe to drive 300 miles are appreciated.

srb1194

I'm no expert on the 350 but my other experience tells me no. I personally would wait for replacement filters before heading out for that long of a trip. Just an opinion. Best of luck to you.

GLK Super Fan

Why don't u pop the engine filter out and check it
If you really wants to use the vehicle, clean the filter with water and detergent, make sure u dry it completely after. There are lots of people done it online(search in YouTube) with cheaper vehicle like civic and corolla. Or bring the vehicle to the service department first thing in the morning to get a replacement part. I will probably clean the MAF sensor in case the oil got on it. Good luck. Sorry for ur pain.

By the way, similar story happen to my brother in law's Audi S5, he took it to fast lube place and they over filled the oil which caused oil leak everywhere. Sometimes it worth to pay someone actually care to work on the European vehicle. That just my 2 cents.

bop11

Sounds like the Valvoline guy forgot to remove the old oil before filling it with new stuff. This would blow out the breathers and anywhere else. It may have moved the oil seals on the crank and other locations. The engine dies because the sensor are full of oil. The oil surely was high enough to be sucked into the combustion chamber. This sounds like a legal matter between you and the Valvoline retailer or the Valvoline company if it is a company station.
I am sure this happens often where one guy thinks the other has drained the oil and the second guy just fills it. Nether of them have probably ever heard of a dip stick. Since most times the oil is vacuumed from the crank case on GLK's, is a strong probability. You did not mention any foam or abnormal color, so it doesn't sound like a head gasket.
Main problem is going to be leaking oil seals which have been pushed out of position by higher than normal oil level and pressure.

Steven Solomon

Thanks to all for your help. I pulled the filter as you suggested and the cartridge appears brand new, so at least they did that correctly. The oil burning and smoke have stopped, the air filters were not saturated with oil. However, I did take the car to M-B dealer to have it checked out and he reports small oil leak and many other problems. It never leaked before, but I don't know that I can fully blame Valvoline since the car has 240,000 miles on it. Maybe they hastened seal failure, but it would be hard to prove one way or another. The truck needs a whole bunch of work anyway-front and rear suspension, motor mounts, tranny mounts, and the tranny is starting to get wonky. Also needs alternator, intake manifold and a "Prem Air" sensor that is causing permanent CEL (part of the PZEV system). So time for a new daily driver, but my son and I will make this our winter project and fix everything, then we'll keep it as a spare, and for winter use-it's great in the snow. Really trying for 500,000 miles on original engine and tranny. I happen to really like the way it looks and drives, and at 240K miles no squeaks, rattles or other problems, and we've had very few problems since we bought it in 2010.

Alternator and intake time consuming, but not difficult. My question is about this Prem Air or engine temp sensor that is mounted to the radiator (small black plastic box with clips that hold it in place and a plastic probe with a wire in it that fits into a receptacle in the radiator), and apparently this cheap plastic probe breaks off and throws a CEL. Part is close to $900 from dealer (less if I give them the core) and needs to be glued in with Loctite. I don't even know what this part's purpose is, since the car already has water and oil temp sensors, but I'm stuck with it and can't pass inspection in NY with a CEL. Anyone else had one of these fail?