[sixer]

Hi all,
Does anyone know what this pipe is? I have had a engine rattle for a while now and found that this pipe had come out of its clip. Unfortunately it has rubbed against the brake pipe next to it causing the black coating to be rubbed through.

Any idea what the pipe circled is?

[gclions]

That looks like the vent from the gas tank if I have it located correctly.

During my many attempts to create an intake setup I damaged the one on my F10, I want to say it was $50 to replace going from memory. The one on my F10 is a teal color, but judging from the picture, it's in the same relative location.

Not sure where yours would go on the 520, but on my 550 it goes to a solenoid mounted to the driver's side intercooler, where I believe the function is to pull excess fumes off of the tank, by allowing them to be drawn into the intake. I'd need to do some more reading to make sure I have the function correct.

If you have a rattle, it might actually be a sputtering, sucking noise as air is being drawn through the hole. I'll do a little looking to see if I can confirm what I think it is.

[sixer]

Thanks for your reply. The pipe is located in the right side of the engine when looking into the engine bay. One end disappears into the wheel arch and the other to a Bosch labeled silver unit attached to the engine. The pipe is not ruptured and the rattle has now gone. The pipe was hanging loose from the plastic clip retainer causing the rattle.

I am just keen to be sure what this pipe is for as a very small (pencil head size) piece of pipe covering has been rubbed through. If this is a critical pipe it's getting replaced 😀

[gclions]

Can you snap a picture of the Bosch control unit?

[sixer]

Here is a close up pic with the pipe arrowed.

[gclions]

I've spent a great deal of time on realoem, no luck confirming my thoughts. What year is your 520d? Europe?

[sixer]

Yes a UK spec 2014 520d touring twin turbo.

[Pimpsy]

That looks like a high pressure fuel pump, and if I had to guess that's either the high pressure line going to the injectors, or the overflow line.

See under injection on this page. http://www.auto-innovations.com/site...7t28print.html

Can't find a good EPD to confirm, but someone else probably can.

[Pimpsy]

Bingo. Fuel return line. http://www.realoem.com/bmw/enUS/show...diagId=13_1227

[sixer]

Thanks so much. I will be taking this to the dealers tomorrow to get it sorted the silver metal line is showing through the plastic sheath..