[32valves]

For the last few weeks my car has been blowing oil pass the filler cap and oil smoke out the tail pipes. It doesn't do it all the time but enough where I? have to add oil and clean the engine compartment. I'm thinking it could be over boosting because I? don't think I? have excessive blow by.

[335dsleeper]

Are you 100% it’s coming from the filler cap?

I recommend looking at your small turbo. Might be hard to see without removing the heat shield but, look and see if there’s oil on or around the center section. My HP turbo seal failed last Friday. It dumped oil in the hot and cold side of the turbo and out of the compressor cover, which coated the valve cover, filler neck, turbos and chassis with oil. I also had blue smoke on startup and intermittently while driving.

I swapped the HP turbo last Sunday and it’s solved my problem. HP turbo was fine, no excessive play or any obvious issue other than dumping oil into the hot/cold side. I guess the seal just let go.

If your turbo is fine and your filler cap’s sealing properly, you might have a more serious issue with the bottom end.

If boost is causing oil to ventilate, you do have a blow-by issue.

[335stoner]

smoke out the tail sounds like a turbo seal... you could easily check by unclipping the intake at the EGR... I know there will be oil, but there shouldn't look like someone added oil to the intake...

also newest word on the street is the intake gasket leaking inside the valve cover making oil go and not go where its is supposed to

[32valves]

I'm going to get a new oil cap and take the engine cover off and see what's up

[Torqu3]

Could be a valve cover gasket issue as well. At low temps it'll spew oil everywhere and smoke out the tail pipes. Once it warms up the oil stays where it is supposed to be.

[32valves]

Originally Posted by Torqu3

Could be a valve cover gasket issue as well. At low temps it'll spew oil everywhere and smoke out the tail pipes. Once it warms up the oil stays where it is supposed to be.

That's a thought, when this happens I? also see oil dripping off the down pipe too.

[335dsleeper]

how does a bad valve cover gasket cause smoke out of the tailpipes.

Originally Posted by Torqu3

Could be a valve cover gasket issue as well. At low temps it'll spew oil everywhere and smoke out the tail pipes. Once it warms up the oil stays where it is supposed to be.

[32valves]

I? hope it's not the hp turbo.
I'm guessing that's the top one?

[335stoner]

valve cover gasket is what I meant.. oops

[335dsleeper]

How does the VC cause oil in the tailpipe?

I don’t understand how a leaking valve cover gasket gets oil in the exhaust.

Can someone please explain.

Originally Posted by 335stoner

valve cover gasket is what I meant.. oops

[32valves]

I? have no idea but I? would know if it were leaking

[335dsleeper]

I get the valve cover could leak and drip on the exhaust manifold, downpipe and even turbos but, I do not understand how oil from a leaky valvecover gasket would make its way out of the tailpipes.

[335stoner]

the swirl flap part of the intake bolts to the actual head. the main runners of the intake bolts to the valve cover and that has the part that attaches to the head. the head to cover gasket seal goes bad. when boost goes up it leaks past and fills the valve cover with some boost that will force oil where it is not supposed to go like the oil cap or excessive oil out the breather back into the intake... turbo seals can also put oil in the intake

[335dsleeper]

Ah, gotcha. I forgot about how the top runners bolt to the valvecover. It’ll be interesting to see if that’s the cause or not.

Originally Posted by 335stoner

the swirl flap part of the intake bolts to the actual head. the main runners of the intake bolts to the valve cover and that has the part that attaches to the head. the head to cover gasket seal goes bad. when boost goes up it leaks past and fills the valve cover with some boost that will force oil where it is not supposed to go like the oil cap or excessive oil out the breather back into the intake... turbo seals can also put oil in the intake

[32valves]

In another thread I? replaced the breather at the rear of the valve cover.
That is what started pissing oil out. And it seemed good for a week then I? put the engine cover on and all the bottom shields on then this week it started again but oil cap and somewhere in the rear cause the down pipe is wet too.

[335stoner]

sounds like a good candidate for a leaking valve cover gasket? sounds like your first week point was the breather.. then after that its the cap gasket... you should pull the intake off from the air filter to the small turbo. that is where the crank vent drains into.. I would be curious to see how much oil is passing through the vent tube??

[32valves]

Yeah I? will do that this weekend

[32valves]

Originally Posted by 335dsleeper

Are you 100% it’s coming from the filler cap?

I recommend looking at your small turbo. Might be hard to see without removing the heat shield but, look and see if there’s oil on or around the center section. My HP turbo seal failed last Friday. It dumped oil in the hot and cold side of the turbo and out of the compressor cover, which coated the valve cover, filler neck, turbos and chassis with oil. I also had blue smoke on startup and intermittently while driving.

I swapped the HP turbo last Sunday and it’s solved my problem. HP turbo was fine, no excessive play or any obvious issue other than dumping oil into the hot/cold side. I guess the seal just let go.

If your turbo is fine and your filler cap’s sealing properly, you might have a more serious issue with the bottom end.

If boost is causing oil to ventilate, you do have a blow-by issue.

How did you diagnose the turbo seal shit the bed?

[32valves]

I? power washed it yesterday but drove it today I? was smoking out the exhaust today.

[335dsleeper]

^ I think you have a compromised valve cover and it's pressurizing your crankcase causing oil to push through the turbo seals and the CCV side into your compressors.

I spoke with a turbo re-builder yesterday, he said the HP turbo is very stout and has very strong seals. He mentioned it's very unlikely for the seals to blow during normal operation but that pressurizing the crankcase would cause oil to enter the compressor and turbine side of the HP turbo, which is what I experienced.

I think i'm experiencing the same exact situation with my X5 as you are with your 335d. I prematurely swapped the HP turbo as I found oil in the compressor and turbine side and even though I knew it was incredibly unlikely for both seals to blow simultaneously, I swapped it out. I'm going to R&R my valve cover gasket (ordered today) and reinstall the original HP turbo. After thinking about it, I'm 99% i have valve cover issue and as a few others mentioned, you likely do too.

[32valves]

The gasket to the head or the gaskets to the flapper ports?

[32valves]

Got oil running down my down pipe, and the oil seems to be up higher than the turbos. But it hard to tell what's going on. And it's oil soaked underneath.