Gen2 Oil Consumption

Hey all,

Have a 2012 ms3 that’s suddenly developed a thirst for oil. I’m the original owner and have regularly changed the oil every 8000km. Car currently has 207000km of good oil’ highway miles on the odo (I cry every time)

Car is very lightly modded with CS sri+tip and a UR cbe. I was about the finally start putting some mods into it this spring but it all of a sudden had a vvt-like rattle at startup.

Checked the oil and the dipstick was bone dry. Dumped what was left in it (was down almost 3l of oil) and filled it up with fresh synthetic. Noise was gone right away, but now it’s burning oil like crazy. I’m going through about half a litre every 100-150km of highway driving. Seems to burn it a bit faster if I use the turbo.

The car runs absolutely fine and there’s been no difference. I’ve had a look around the block and can’t seem to find any oil leaks. It had a starting hesitation but before I even got a chance to diagnose it the CEL came up for p0442 which ended up being the purge valve by the charcoal canister after I smoked the system. My oil issue came up about two weeks later, but might just be coincidence.

Cars been well taken care of and never beat on. It’s daily driven with a good 150km commute currently. I pulled the plugs and every single one had oil on the tip. Piston head looks to have some oil residue. Did a “dry” compression test and it came back 190-195-190-195. The wet test came back with exactly the same numbers give or take, probably due to the amount of oil that is already making it into the cylinders.

I have a very mild amount of white smoke from the exhaust once the cars warmed up but only on deceleration. It’s not smoking nearly enough to see it from the mirror you have to be at the rear end.

I was planning on putting a forged motor into the car if the rings were bad as the car is in extremely good condition otherwise, but the compression test has me thinking the block itself might be good. I should add the valves have never been cleaned, and I do not have a egr delete or a catch can. I wouldn’t think badly gunked valves would cause this but to be honest I’m not sure.

I plan to do a leak down test next up. I fully expected one of the cylinders to have less compression, but what’s the chances of all the plugs having the same oil buildup and the numbers being so “good”

Any thoughts? Valves? PCV? BNR time?

 

Are you still using the original K04 turbo?

 

Stock turbo yessir. From what I’ve read online I’m fortunate that it’s still kicking but I’m basically stock.

 

Ok once I let the car idle for a good 5 minutes she smokes pretty good on acceleration. Just keep getting more and more smoke as it warms up.

Guess I’m in the market for a k04 upgrade?

 

Pull the downpipe and check for gobs of oil. Or the intake piping. Your oil consumption could just be a bad turbo sucking oil through the engine.

edit: intake post turbo piping (so TMIC or Intake Manifold for you).

 

Turbo is the likely culprit

 

Can’t get my hands on a leak down tester locally so rather than wait for Amazon I’m brining it into an engine builder shop to have it tested. Will post back, but at this point I’m hoping it’s the turbo and not the rings lol

 

...taking car to engine builder shop hoping they tell you it doesn't need a rebuild? Isn't that the example in the dictionary next to conflict of interest?

 

Sorry it’s mechanic shop specializing in restoration engines on classic muscle. I’m rural so not many options. Its that or the local autozone equivalent for us in Canada which I don’t trust to even rotate my wheels or change my oil. My mechanic doesn’t have a leak down tester or I’d go to him :/

You make a very good point though, if the results aren’t good I’ll get a second opinion. Very heavy bias for sure...

 

Pulled the silicone connection between the IC and the k04. Inside the connection had a film of oil, but the turbo pipe that it connects to was covered in oil around the outside. The inside of the turbo was perfectly clean. In the photo the oil looks super old and caked on but it’s just the photo, oil was pretty black but wipes right off. Was mixed with the fresh synthetic that’s in it. The pipe side of the IC was clean but I’ve had it apart 5-6 times this month.

Short of pulling the intake on my day off I’ll see what the leak down comes back with and go from there? Noticed a clamp on my intake needs to be replaced anyway. Just don’t have the time right now to pull the manifold or the downpipe.

I appreciate anyone lending some advice, thanks a lot.

 

Was mixed with the fresh synthetic that's in it you say? Wouldn't that imply a reasonably large leak?

If you pull your throttle body off you can get a paper towel into the intake manifold without taking the entire manifold off. Good as any way to check for oil pooled in there.

 

Will pull the tb and check tomorrow night. When you say imply a large leak...you’re thinking leak from where? Super unnerving to me that the inside of the turbo is clean...gravity tells me that the oil is coming from the inter cooler into the turbo...?

FWIW I drove it around for awhile today staying out of boost and it didn’t move a bit on the dipstick when I checked it after the motor cooled down. I’m sure this is a stupid question but if I stay out of boost and the turbo seals are leaking, it would logically burn less oil than if I loaded the turbo up.....right?

 

I'm no turbo seal expert, but I'd guess that if you are loading up the turbo it will apply more force to the shaft and bearings...and would allow more oil leakage. (again, am no expert)

Large leak from seal on turbo into the intake air stream. Air flowing in the direction of the intercooler, with the kung fu slicing action of the compressor wheel might just overcome gravity.

 

What's the turbine on the intake side of the turbo look like? Likely some oil pooling there.
Like jsmith said check TB inside intake.mani with a rag.

Once the turbo seals go it starts leaking lots of oil which looks like is happening to you, most likely new turbo time.

Sometimes running 5w40 instead of 5w30 can buy you some time, but my guess is you're past that point.

 

Long ass Update:

So I checked the manifold there was a bit of oil residue but it wasn’t pooling or overly excessive amounts. I checked all the piping and made sure everything was seated, and discovered one of my t-bolt clamps just before the turbo had snapped. The pipe was still connected and didn’t sound like it was leaking, but that’s probably coincidence anyway.

I did pull my filter off and give it a good cleaning. Let’s just say it was a bit overdue. Or a lot overdue. I ordered a new one from CS as it’s almost 8 years old, probably wouldn’t hurt.

Let it dry overnight and since doing so my oil consumption disappeared. I actually gained a tiny bit of oil over 300km...

Brought the car into the shop today and the guy let me come in and watch the work being done. He pulled the plugs and they were perfectly clean, no oil at all. The pistons still had oil residue. The leak down came back at ~3% across all four cylinders.

Mechanic said the air filter couldn’t have caused the amount of oil consumption I was seeing, but can’t think of what else could cause the consumption but then also cause it to vanish suddenly. Only ideas he had is the oil rings could still be going or overfueling.

The cars long commute will be coming to an end shortly, so I’m going to finally pickup an AP and internals. I’ll monitor the oil and the engine and go from there. Even if it needs a rebuild they are things I obviously can reuse. She’s a bit old to be putting down any crazy power as my priority is reliability, but from what I understand I’m better off with a mild protune.

Unless there’s something that’s been missed (only thing I haven’t checked is the PCV), I’m gonna just keep an eye. Thanks for the advice and help folks it’s much appreciated. If I run into any issues I’ll post back in case it helps someone in my shoes.

 

Still oil consumption from the turbo.. may not seem like much but it'll add up


Edit: I realized that you mean air filter and yes that should probably be done more than every 8 years lol

 

If it was that dirty and you were creating a vacum by spooling the turbo then yes you could have been sucking oil out of the turbo.