[vetofunk]

Hey Guys,

My 2007 335i has 113,000 miles on it and it used to be I will have to add 1 quart of oil every 1-1.5k miles, now it's like every 500 miles it's low and I have to add a quart of oil.

Also...I no longer have any boost...it's like a 328i or something.

Could these two things be connected? I took it to a mechanic about a month ago and he didn't see any error codes or notice a leak.

I did have a GIAC Stage one re-flash done around 25k miles.

Ideas?

Jeff

[vetofunk]

And with the oil, could it be because I am using Castrol Syntec 5W-30?

[vetofunk]

bump

[DJtoad]

I'd start with a compression test. That's a lot of oil to go through and if you're not leaking it, you're burning it.

[FrankyGTR]

wow thats a lot.sorry to hear. its not the castrol,keep us posted please.

[FL335]

Yeah, bring it back to the Indy and have him run a leak down test. Let us know what happens. GL

[Jklad]

Probobly completely seperate issues. Nothing to freak out over.

For the oil issue:
Is there oil accumulation on your floor under the car?
Check your ofhg, oil pan, valve cover gasket, and rear seal. Something's probobly been leaking pretty badly for a while.

Your power issue is likely a seperate issue. Any codes? Check and replace each of your vacuum lines if you've never done this yet. At 113k miles its totally common to have oil leaks and dried up vacuum lines that should have already been replaced.

The only way the two are related is if you have a bad valve cover gasket leak that is leaking into the spark plugs, but this would cause misfires.

[vetofunk]

Originally Posted by Jklad

Probobly completely seperate issues. Nothing to freak out over.

For the oil issue:
Is there oil accumulation on your floor under the car?
Check your ofhg, oil pan, valve cover gasket, and rear seal. Something's probobly been leaking pretty badly for a while.

Your power issue is likely a seperate issue. Any codes? Check and replace each of your vacuum lines if you've never done this yet. At 113k miles its totally common to have oil leaks and dried up vacuum lines that should have already been replaced.

The only way the two are related is if you have a bad valve cover gasket leak that is leaking into the spark plugs, but this would cause misfires.

When I took it to my mechanic, it threw no codes. He thought it could be the spark plugs...changed them and no fix. So you think it could be vacuum lines?

[Jklad]

Originally Posted by vetofunk

When I took it to my mechanic, it threw no codes. He thought it could be the spark plugs...changed them and no fix. So you think it could be vacuum lines?

At this point, with no codes, it's just speculation. But, at 113k, if you havbt replaced your vaccum lines yet, I'll bet at least one or more has a small crack or tear. A small leak would not throw a code, but you'll feel it as a loss of responsiveness/slower to boost. You should replace them all (intake side and turbo side). There's a diy on the n54 subforum with diagrams. Search for 'vacuum lines'.

It's cheap and easy to do yourself (except maybe the lines going from wastegates to the solenoids). $120 in parts and a couple hours.

[Red_Bean_Bun]

Check the air manifold pressure values ...... And wastegates

[335coupepr]

Originally Posted by Red_Bean_Bun

Check the air manifold pressure values ...... And wastegates

Your turbos are bad....You have a bad turbo seal, the hot side.

[Get lit]

Also look into doing a leak down test. 1qt every 500 miles is a lot of oil going somewhere. If no leaks on engine then oil is being spent internally. Valve seals, piston rings, turbo.....