WestCoasterBC

Hey, long time reader, first time poster.

I have a 2010 ML350 Bluetc, 191,000kms. Lately I have noticed a lot of oil consumption, somewhere in the neighbourhood of 1L/1000kms. There is no oil on my garage floor so it isn't leaking so I must be burning it. It has a Malone stage 1 tune with DPF, Adblue, EGR, intake swirl flap removal. Not sure how to determine if it is a turbo issue or my rings. I have taken the exhaust side of the turbo off and there was a fair bit of oil in it. I saw a good test was taking that off and putting white paper in front at 2000rpm to see if it got oil splatter and we tried that, it ran quite rough doing that but no oil splatter a hell of a lot black smoke though, more than when it was still on. I also brought it in to get my passenger seat sensor replaced and they mentioned that my chain is making noise and needs to be replaced shortly. Not sure if that makes a difference for this. I have seen people talking about a blowby test and I am not sure exactly how to do that or why to do that. How can I determine if is my rings or turbo or something else?

B34chBum

From what I recall the stretchy chains were some 2010s and some 2011s.
Roll your windows down the next time you start it in the morning. If you hear extra nasty noisiness clacky rough running, which then smooths out after 5-10 seconds, please listen to your mechanic, too.
This is more important than oil consumption. but could aggravate that, too.

On the other hand, if car starts off smooth and stays that way time to take a look around. Most common oil loss that you don't see anywhere, is from the PCV valve on the back end of the passenger valve cover.
If you pull off the right hand air cleaner and the foam cover / sound deadening, you'll see it back there.
A diaphragm inside it splits, and it doesn't hold the excess pressure back just starts puking up oil/crankcase fumes, which then go into the air intake.
If you're sold on the mechanic changing your timing chain, go for broke and have the PCV valve changed too.

Good luck!

WestCoasterBC

Could that have also be the reason why when I am going uphill at a steady speed it surges a bit? The car will drop in rpm a bit and then go back up to where it was.

B34chBum

Hard to say.
Buy a scanner of have your mechanic scan for trouble codes, if you're seeing a drivability issue. The is popular on these forums, and not unreasonably priced.
Hesitation or inconsistent power could be fuel supply, injection control / quality of injectors, boost control module (is an electronic servo mounted on the turbo).

The timing chain getting stretched could affect well, engine timing - but I would think the main symptom would be drop in fuel economy, at least until the timing was way off.
As soon as the oil pressure comes up the chain tensioner would take up the slack in the chain.
(Others who've had to deal with this might chime in on other symptoms they saw)

WestCoasterBC

Here is the cold start this morning. Does it sound like the timing chain is loose? Should I get it done. $2400 at the MB dealer and oddly $4200 at the local independent shop.


Just did a blowby test as well. Looked good so I will have to assume that the seals are good. I think I will replace the PCV and the turbo and since I am in there do the oil cooler seals and see how it goes.