Oil in the Air Intake Elbow

[jaz525i]

93 M50 142,000mi

Had to replace a vacuum line and took off the intake elbow to gain access to it. While it was off I noticed a considerable amt of oil in there and a bit in the throttle body too. What line would allow oil to make its way up there and any other clue as to what something like this could be?

[DaveVoorhis]

The crankcase ventilation line on the lower left side of the intake elbow is the entry point. A bit of oil there is normal, as the oil vapour sucked out of the engine condenses in the intake. If you've got (or had) a vacuum leak, it may be a bit worse, as the oil vapour is more likely to condense than get sucked into the engine where it belongs.

[Jon K]

Yep, normal.

[OhioTouring]

It is good to know this is normal. But, there are 2 tubes that come off of the head.

1) Goes to the throttle body boot. It's the bigger of the 2.

2) Where does this one go. Mine is dangling.

[Jon K]

There are two hoses going to the 90 degree TB boot - one is the crank case vent as mentioned, which goes to the intake manifold, passes under, and hits the valve cover. The other is the larger one closer to the firewall and is the idle valve hose. If thats hanging off, you have a massive air leak.

[OhioTouring]

I attached a couple of pictures to help see which two hoses I am mentioning. For some reason, the Bentley manual does not have vacum diagrams, or I may just be missing them somehow.

[Jon K]

I attached a couple of pictures to help see which two hoses I am mentioning. For some reason, the Bentley manual does not have vacum diagrams, or I may just be missing them somehow.

I just happen to have a [ghetto] diagram of this. The small dangling one is simply a vacuum line - there is a plastic insert that goes into the manifold directly behind the throttle body (if you were standing over driver fender) on the underside with a 1/8" nipple coming out toward the front of the car, that hose hooks up there, its to draw vacuum/fumes out of the crank case at idle.

http://www.blowneuroz.com/mygallery/Miscellaneous/pcv_vent.jpg

[jaz525i]

I attached a couple of pictures to help see which two hoses I am mentioning. For some reason, the Bentley manual does not have vacum diagrams, or I may just be missing them somehow.

That small dangling hose is what I replaced. Its some kind of vacuum hose for the tranny. My car (automatic) was shifting sloppy and was hesitant. That hose was dry and cracking and from a dead stop, the car was initially starting off in what felt like 3rd gear. I also got a TRANS light on my dash display. Once I replaced that hose, its shifts hard again.

[OhioTouring]

Thanks a ton. Have been wondering where that hose connects for a while now.