Crankcase vent (PCV) plugged (again)
Has anyone else had a similar issue?
From my point of view I have a couple options... I will contact the Iowa City dealer and ask if they will step up and help me out with the repair since it appears to be a reoccurrence of an issue which should have been addressed within warranty. I suspect this will be long shot but who knows.
I don't mind wrenching on this stuff myself, but tech manuals seem to be unavailable to the general public. Where do folks find tech information?
Thanks in advance.
Has anyone else had a similar issue?
From my point of view I have a couple options... I will contact the Iowa City dealer and ask if they will step up and help me out with the repair since it appears to be a reoccurrence of an issue which should have been addressed within warranty. I suspect this will be long shot but who knows.
I don't mind wrenching on this stuff myself, but tech manuals seem to be unavailable to the general public. Where do folks find tech information?
Thanks in advance.
I recently had the same issue with my C300 and it is just out of warranty. The problem occurred before the warranty expired but it was intermittent and the one time I left it at the dealership overnight, the CEL was gone in the morning. It got worse recently and they quoted me 1700CAD to fix it but told me to come back if it is on all the time. A few days ago, the light came on and the car stalled on me a couple of times and there was an oil leak under the hood with white smoke coming out of the exhaust and a burning oil smell. I took it to the dealership and they haven't looked at it yet but I wanted to get your input as the problem is the same issue you had with the white smoke.
And what did you end up doing regarding the warranty? I had an indie mech tell me that he was trying to get it fixed under warranty from a service rep he knows as the problem is a known issue for those cars.
Last edited by Sador Efrem; Dec 14, 2018 at 06:57 PM. Reason: Spelling

I've always believed it to be induced by the cold weather and condensation in the valve/vent line. I live in the North East where it gets cold too. We get some valves with an insulation wrap/tube on them and some without...
I had a '15 C300 and always let my car reach operating temperature before driving. I also drive the highway everyday. I feel that I see this issue more common on vehicles that don't appear to often drive many miles.
I actually had one yesterday where the valve was stuck and the engine oil had actually coated the intake pipe and turbo. This could have been why you seen smoke, but I've never seen smoke or drive-ability concerns from it.
Just two cents on this.
Trending Topics
- CEL on at 91,000km but went away after a day. Code was for “crankshaft rebreather valve” but since light was off, kept driving
- Week later mid-drive, started running rough and next intersection started blowing very thick white smoke out exhaust.
- Flatbed to dealer, needed a new engine as cylinder 1 had zero compression and had scratches on the cylinder wall.
Story has a happy ending after all, but was without the car for quite a while.
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I've always believed it to be induced by the cold weather and condensation in the valve/vent line. I live in the North East where it gets cold too. We get some valves with an insulation wrap/tube on them and some without...
I had a '15 C300 and always let my car reach operating temperature before driving. I also drive the highway everyday. I feel that I see this issue more common on vehicles that don't appear to often drive many miles.
I actually had one yesterday where the valve was stuck and the engine oil had actually coated the intake pipe and turbo. This could have been why you seen smoke, but I've never seen smoke or drive-ability concerns from it.
Just two cents on this.
Mine happened at around 43K miles and was a related issue as you stated. Thankfully it hasn't come back yet and im at just about 60K miles




