I used this thread to help isolate my "tigten gas cap" alert I've had for some time:
https://5series.net/forums/e60-discu...message-46188/


I replaced the cap twice, still get the error on iDrive and a CEL - pulled the code 'P0442' (small evap leak).

So I removed the wheel liner on the passenger rear side, and discovered that a pretty big area of the liner had been shredded. I suspect it was a tire that bulged on me a few months back, it wore away the fender-liner, and exposed the plastic "evap" hose connected to the DMTL.

Initially, I took off the fender liner and patched it up with some plastic. Them evap hose running from the DMTL was almost split in 2, so I got a piece of 3/4" vinyl tubing, and wrapped the frayed ends of the split hose into the new casing. I made sure it was secure using electrical tape, and a small ammount of silicone sealent. It's not the best-looking fix, but Im somewhat certain it's not leaking.

So I drove around yesterday, and thought I had it fixed. Took 3 20min drives, and the alert never came back! Hoorah!

Well this morning, I went to get brealfast, and sure enough the "Check gas cap" and the CEL came back!!!



I *think* it's #7 in this diagram, but it's hard to tell. It's not the white & rigid fuel line, but rather the hollow plastic "evap" hose that is pinned up inside the wheel well.

I think my DMTL is OK, because when I turn my car off, I can hear some type of motor stay on, once the car is turned off. It's right at the gas tank, and from how I undersatnd this to all work, it seems like it's staying on because there is some sort of leak in the system.

I'd suspect the hose is going to be cheaper to replace than the unit, but maybe not as easy? Is there anything I can do to rule out the DMTL other than just replacing it? It's a $200 dealer item, $120 online. If I can find out the part # for the hose, I bet it's even cheaper.

 

So I think the part I need is the "Rear Scavenging" Line. According to this link:

RealOEM.com BMW E60 530i Activated Charcoal Filter/FUEL VENTILAT

I cant seem to find a real picture, but I'm pretty sure this has to be it because it's held in place with part # 9 & 10 (clips)

 

Ronmexico -

Did you have any feedback or updates from your troubleshooting? Was it the hose or did it turn out to be something else?

Thanks in advance!

Yihchau