2nd Gen R56 Cooper S Most liked posts in thread: Oil overfill

Running out of ideas.... Somehow you are either continuing to add oil to your combustion..... The question is.... Is it latent oil that has coated your intake track and just continues to flush through the system? Or is it from another source? Did you notice if there was oil inside the intercooler?

 

Not sure if this helps.

Did you check your catalytic converter for oil clogging?

If it is clogged then you would see increased back pressure measured by a back pressure gauge which screws into the O2 sensor port on top of the cat pipe (closest to the turbo). I was told by 2 shops that greater than 1.5 psi is no good. (Can't find verified documentation
However ).

You saw that you redid the turbo not exactly what. Did you rebuild
It, replace it etc?

The oem turbo uses a journal bearing
So the turbine shaft floats in a bath of oil. One theory about seal failures is that the increased back pressure from the cat being clogged puts too much pressure on the turbine shaft and wears out the metal clip seals holding the shaft in place. This allows for lateral movement which allows oil to escape the bearing cavity pushing
Oil to both the intercooler and the catalytic converter. That is what happened on mine and I replaced the cat, turbo, intercooler.

Could this smoke be coming from the oil in the cat?

 

If your PCV is not allowing blow by gases to escape into the intake either on the throttle body port or turbo inlet port your crankcase pressure can cause oil to backflow into intake or exhaust. Are you running an OCC?

 

Plug the open hose ends so the engine doesn't go lean, but leave the valve cover connections open and you should be able to run this test...

 

Rubber stoppers.... Lowe's has them....

Plug first.... Then start the engine.... If not, you will throw a code for running lean.... The leak will be after the A/F sensor..... Soooo, un-metered air will enter the systen and your ECU won't like that...

 

Yes you do.... It's called a MAF (Mass Air Flow sensor).... I just did the A/F sensor as shorthand...

It determines the air mass going to the engine so the ECU knows how much fuel to add at the cylinders adjusted by input from the O2 sensors....

Any leaks to this measuring system show up and the ECU attempts to compensate.... Which is where the stoppers come in....

 

Sooo you are saying you don't have #13?





Well...... Somewhere your ECU determines the proper fuel ratio to run the engine even in
South Africa...

You have two choices.... Pull the hose ends off the valve cover and plug the hoses themselves.....

Don't plug the hose ends and you will probably introduce non metered air and generate a CEL.... with a lot of engine stumbling....

Hose plugs are cheap and you don't need to deal with throwing a code...

Your choice....

 

So you have this....

Then the small hose on #10 might suck in dust......

The other hose on the valve cover goes down to the throttle body on the intake.... I'd suggest you plug that one then and run you test...