[cocogirl]

I have some oil on top of this line. It looks like brake fluid since it is clear. Maybe is engine oil but I expected it to be more brown/black. I cleaned the line and it come back the next day. It located on the driver side behind the steering reservoir.

I can't find it on RealOEM. Can someone tell me what this line is? Vacuum line?

[gbalthrop]

Originally Posted by cocogirl

I have some oil on top of this line. It looks like brake fluid since it is clear. Maybe is engine oil but I expected it to be more brown/black. I cleaned the line and it come back the next day. It located on the driver side behind the steering reservoir. I can't find it on RealOEM. Can someone tell me what this line is? Vacuum line?

I don't see anything similar on my 2007 328xi E91. I certainly do NOT think it is a vacuum line. Only vacuum line I know of in that area is the hard, larger diameter, smooth (NOT corrugated) black plastic tube that runs forward from the brake booster at the firewall to the Vacuum Pump located under the OFH (Oil Filter Housing). What you show/ circle in your top photo is flat (between the corrugated "Loom" segments), and if that were the booster vacuum hose being sucked flat by the pump, you would have NO power brake assist.

It looks like a wiring harness Loom to me, and your bottom photo appears to show it joining other wiring at the left fender gutter, beside the Left Strut Housing, so it MUST be a wiring harness/Loom.

As for the fluid, you have P/S fluid in the reservoir shown in the top photo, and CHF-11S is relatively clear. It looks as though the reservoir has been wiped below the cap on the side toward the harness. The brake reservoir and lines are NOT within a foot or more of that area on mine. Simply Condensate/ water perhaps? I would watch fluid level in P/S reservoir and use a paper towel to wipe any liquid off the harness, checking the paper towel for any color or odor.

Please let us know what you find,
George

[CTinline-six]

What year and model car to do you have (325i, 328i, 335i, etc)?

[cocogirl]

Originally Posted by gbalthrop

I don't see anything similar on my 2007 328xi E91. I certainly do NOT think it is a vacuum line. Only vacuum line I know of in that area is the hard, larger diameter, smooth (NOT corrugated) black plastic tube that runs forward from the brake booster at the firewall to the Vacuum Pump located under the OFH (Oil Filter Housing). What you show/ circle in your top photo is flat (between the corrugated "Loom" segments), and if that were the booster vacuum hose being sucked flat by the pump, you would have NO power brake assist.

It looks like a wiring harness Loom to me, and your bottom photo appears to show it joining other wiring at the left fender gutter, beside the Left Strut Housing, so it MUST be a wiring harness/Loom.

As for the fluid, you have P/S fluid in the reservoir shown in the top photo, and CHF-11S is relatively clear. It looks as though the reservoir has been wiped below the cap on the side toward the harness. The brake reservoir and lines are NOT within a foot or more of that area on mine. Simply Condensate/ water perhaps? I would watch fluid level in P/S reservoir and use a paper towel to wipe any liquid off the harness, checking the paper towel for any color or odor.

Please let us know what you find,
George

It is not wiring for sure. I was clean the area and the tube come off. It also has some air escape noise. My brake is fine. That's why I have no cue what that is. Also my P/S reservoir is dry outside and no sign of leaking.

[cocogirl]

Originally Posted by CTinline-six

What year and model car to do you have (325i, 328i, 335i, etc)?

2011 335i

[CTinline-six]

Originally Posted by cocogirl

2011 335i

It looks to me like a vacuum line. Would you be able to follow it and see where it attaches?

Is your car using any oil?

[cocogirl]

Originally Posted by CTinline-six

It looks to me like a vacuum line. Would you be able to follow it and see where it attaches?

Is your car using any oil?

I can't follow the line all the way which required to take things apart. The right side of the line goes to the under DSC module. The left side goes to the engine near the intake manifold.

My car use oil from day 1. Used 1 qt every 3000 miles.

[cocogirl]

Find the picture for N55. Don't worry about the red circle. It has the same line and it look like regular line not corrugated like mine.

[CTinline-six]

I would try inspecting that corrugated line for cracks. It might have gotten brittle and developed some cracks which are leaking.

[weehe126]

That line is for the exhaust valve/flap. It runs from the left side of the valve cover to where you are looking, then all the way to the back of he car. There is no reason it would have oil come out of it. The oil is most likely being thrown onto it from somewhere else. Check and make sure the oil filter housing isn't leaking into the belt, which can throw oil in that direction.

[cocogirl]

Originally Posted by weehe126

That line is for the exhaust valve/flap. It runs from the left side of the valve cover to where you are looking, then all the way to the back of he car. There is no reason it would have oil come out of it. The oil is most likely being thrown onto it from somewhere else. Check and make sure the oil filter housing isn't leaking into the belt, which can throw oil in that direction.

My oil filter housing is good, free of oil. In fact the gasket was changed 10,000 miles ago. The only thing I'm thinking is brake fluid since I have brake fluid change few months ago. Maybe the shop spilled some and get along to that line.

I want to change that line since it is corrugated. Anymore know the part #?

[CTinline-six]

Originally Posted by cocogirl

My oil filter housing is good, free of oil. In fact the gasket was changed 10,000 miles ago. The only thing I'm thinking is brake fluid since I have brake fluid change few months ago. Maybe the shop spilled some and get along to that line.

I want to change that line since it is corrugated. Anymore know the part #?

It's very possible something was spilled, and since the line is corrugated it is hard to clean. I would try spraying it with brake parts cleaner and cleaning it with a towel to see if the oil reappears.

[gbalthrop]

Originally Posted by cocogirl

It is not wiring for sure. I was clean the area and the tube come off. It also has some air escape noise.

Originally Posted by weehe126

That line is for the exhaust valve/flap. It runs from the left side of the valve cover to where you are looking, then all the way to the back of he car.

I have no dog in this fight, as I don't have an exhaust flap on my N52KP. However, now that someone who has owned an N55 has stated that it is a "line for the exhaust valve/flap" here is the TIS circuit diagram for the Exhaust Flap on the N55 which shows two wires going to the electrically-operated flap. The Red/White wire is a power supply wire from fuse F17 in the Junction Box (Fuse Box), and the Gray/Yellow wire is the ground signal supplied by the DME in the E-box:
https://www.newtis.info/tisv2/a/en/e...-flap/CkWVhbOQ
Here is the installation location of the Exhaust Flap:
https://www.newtis.info/tisv2/a/en/e...cab/1VnYhLHwwS

So BOTH of those wires come from the right/passenger side of the firewall in the engine compartment and have to go to the Left-rear of the vehicle where the Valve is located.

My bet is that if you disconnected one end of the flattened sheath from the round loom, you would find one or both of those wires (possibly with others going to different components), that's Red/White, and Gray/Yellow, inside. I've never seen wires INSIDE a vacuum line, and I've never seen vacuum line that is corrugated like wiring loom.

BTW, BOTH of those wires are small gauge, .75 & .50 mm-squared respectively. However you could probably feel at least two wires inside that flattened sheath without having to even take it apart. Just don't CUT it unless you are SURE you won't cut the wiring.

George