2012 BMW 335i Evap System Description & DMTL Bench Test

In this video, I will describe the BMW Evaporative Emission Control System (EVAP). I will show some ways to diagnose issues with the charcoal canister and the DMTL (Diagnostics Module - Tank Leakage) pump and describe each of the fuel vent hoses and where they go to/come from.

[@Jeff-bw5kw]

Great DIY. Thanks!

[@JRsGarage]

My pleasure.

[@Kolenment]

The fuel fill cutoff and rough idle haven't been resolved? Does this mean the issue could be a clogged EVAP line or maybe with the gas cap?

[@JRsGarage]

I believe I fixed the fuel fill cutoff by blowing out the evap lines. I need another fill-up to be sure. The rough idle is still there. I think it may be a leak in the evap line to purge solenoid so when the solenoid is energized and opens, it introduces a vacuum leak.

[@Kolenment]

@@JRsGarage Did you have to drop the rear exhaust and heat shields to blow out the evap lines?

[@JRsGarage]

No, I opened the gas cap and disconnected the purge solenoid line in the engine bay and blew them out from their canister connections.

[@fraizer2600]

Very interesting do we need to change that charcal after some years ? And that dust filter ? :)

[@JRsGarage]

You can’t really clean out the canister so once it fails (no longer allows air through freely) then it needs to be replaced. The dust filter can be cleaned off. Neither are part of the normal service schedule.

[@DespiertaVe]

I being struggling with VALVE FUEL TANK VENT, i did a bunch of things like smoke test it came out good,no leaks i change the EVAP part that goes in the engine area(2times) and i still cant figure out what’s causing that code.

[@JRsGarage]

Have you tried replacing the DMTL pump attached to the charcoal canister? I’d try that next.

[@DespiertaVe]

@@JRsGarage I changed both of them,still can figure out whats causing that problem,because of that my engine goes in to limp mode.

[@JRsGarage]

Someone commented one time to unplug the purge valve and idle for 10 mins then reconnect, clear the code and drive it around for 10 miles. Not sure how that might help but worth a shot. Are you sure the limp mode is due to the vent valve? Never heard of it causing that.

[@DespiertaVe]

@@JRsGarage yea, its my everyday car so i can feel it when it goes in to limp mode,after that i get the code 2A1A-Fuel tank ventilation system.

[@JRsGarage]

Ok, so it’s something wrong with the entire system. Could be your gas cap. You said you tried smoke testing so you have the equipment. Try disconnecting the lines connected to the evap canister and smoke test them to see if there are any leaks.

[@giedrius2780]

hello. maybe you already found the reason? I have an e70 3.0l n52. it's hard to fill up the fuel, the fuel gun keeps getting cold. and it doesn't work well on idle. after turning off the car after a long drive, something is poking at the back of the fuel tank. thank you very much!!

[@JRsGarage]

My idle is still a little rough. I think the problem is a leak in the purge solenoid line that comes from the charcoal canister. I haven't had time to deal with it fully. The fuel filling is better now after I blew out the vent line in the fuel filler neck. It's not perfect yet. Actually, for some reason it fills well when I turn the fuel gun upside down while filling. I'm not sure what you mean by something poling at the back of the fuel tank?

[@giedrius2780]

sorry, maybe the google translator didn't translate it that way. I have a hard time pouring fuel. and the revs jump on idle. sometimes when I turn on the gear, the revs start to jump sharply. I changed the van solenoids (febi), van filters (oem), I changed the disa valves, I changed the fuel tank valve. the same.thanks

[@JRsGarage]

I would suspect a vacuum leak. There are many vacuum lines so it may be hard to find. You might want to take it to have a smoke leak check.

[@giedrius2780]

thank you. I will try to find out who does this

[@johnb8642]

@@JRsGarage did you get to the the bottom of it bro ?

[@debobmw3996]

Was that throwing you code P1449?

[@JRsGarage]

No code that I recall.

[@TavianM]

Can you make a video on how to replace line 10 please.

[@JRsGarage]

Sorry, I'm pretty sure that would require dropping the fuel tank and I have no plans for that.

[@TavianM]

@@JRsGarage whenever you have a plan to do so can you ? Or do you anyone else who has replaced it on YT ?

[@JRsGarage]

This one may provide some information. I haven't watched it so I'm not sure. kzbin.info/www/bejne/rZaUo6GgbpiDe68si=MaTkmJFYLef-vfFQ

[@miguelgallardo7692]

ME: Fuel low-pressure sensor, electric. 2A15 - ME: Fuel tank ventilation system and purge air system, minor leak. 2C77 - ME: Oxygen sensor after catalytic converter: Signal. Got these codes wondering what it is causing my check engine light to come

[@JRsGarage]

Any one or all of those codes could cause your check engine light to come on. First I would clear the codes and then check them as soon as the check engine light comes on.

[@CarlosMartinez-tp3zl]

I have those codes forever now a 2b3c codes for dmtl system fault. My whole assembly is cracked

[@JRsGarage]

At least that's easy to diagnose.

[@adolfovzqz7365]

Where is the EVAP switching solenoid?

[@JRsGarage]

Do you mean the fuel tank ventilation valve? It's in the engine bay connected to the intake.

[@Brok3n_54]

I’ve had fuel dump into my canister 3 times now …. Any ideas?

[@JRsGarage]

Is there any pattern to when it happens? Perhaps a blockage somewhere causing the fuel itself to leak into the canister instead of just the fuel vapors. Or topping up the fuel past the pumps automatic shutoff?

[@Brok3n_54]

eveytime its happened ive been at the pump and its cut me off half way.. this last time i had gas pouring out from under the car at the pump... i had my canister plus the dmtl pump replaced last year(for the 2nd time) and it just happened to me again about 2 weeks ago. im using a stage 3 precision autowerks fuel pump which might be the cause of all this but i dont see how. i might just go back to stock pump to test it out but im just so lost at this point haha@@JRsGarage

[@Brok3n_54]

a shop also ran a smoke test on the evap line and said it was clear so i dont whats going on@@JRsGarage