[faz]

First time, dealer said they didn't find any issues (code said minor leak of some sort on the gas tank side), and suggested perhaps I left the gas cap not completely closed? I said no way, but didn't want to argue. They reset it.

A couple of weeks later the light came back. This time they kept the car for 2 days and after all sorts of smoke tests and such, they said they found a small leak on some purge valve and replaced some tubing/valve on the front driver side of the engine.

Now, 2 weeks later, again the check engine light is back on. I am taking it in on appointment this Friday.

Anyone else had anything similar to this? I love the car as I looked around to find a manual stick shift, but this check engine light is putting a serious damper on my love level for this car (and the brand).

Any suggestions / tips / things to look at? (that I can ask the dealer to check for me?)

Thanks.

[The X Men]

Seems like you have a problem with your Evaporative emissions control systems. Have the dealer tried replacing the fuel cap already? You said your dealer have already replace your PCV valve, you may have a clogged charcoal canister. Do you top off your gas tank when filling up?

[gatoman39]

This problem surfaced on a 528i during Edmunds long term test:

http://www.bimmerfest.com/forums/sho...d.php?t=549944

[faz]

Thanks for the replies.

The fuel cap has not been replaced, and I don't top off the gas tank by habit, so can't imagine that being the cause.

It seems like the filler neck comes up a few times in these threads, so that might be the cause. I brought that up to my service adviser but he discounted anything that can be read on the internet. I have been around forums a long time to know that I can't rely on everything out there, but at the same time, these forums and shared experiences are a wealth of knowledge that can help in the long run.

I thought I had the service records from the last visit in my office, but I don't have it here. I will look at it when I get home and post exactly what was replaced (purge valve) for others to see.

I will keep this thread updated on any progress. If anyone has any other comments/links/etc. that they can share, I appreciate it too.

Cheers.

[faz]

As promised, here is the info from dealer's notes from the last time:

parts:
13-90-7-636-157 55 fuel tank ventlation valve 13999990
13-90-7-636-131 48 fuel tank breather line:135040



FC:190302 , minor leak detected, smoke tested no leak noticed at DMTL pump/canister/gas cap, under seat sending unit, lines, no leaks found.

Forman advised to check tank vent valve, removed air filter box and rechecked/smoked vent valve and found small leak at valve via smoke test. Diag Code D1330_B0000000_02_001. Replaced tank vent valve with in conjunction line and performed DMTL leak test. Test pass no leak detected, cleared FC memory and test drove.

[faz]

Just an update: picked up the car today from the dealer. Minor leak detected, after contacting BMW, dealer was instructed to replace the DMTL pump even though dealer had not seen any error codes from DMTL pump.

The pump has been replaced and the minor leak is no longer present, so they are hoping that this has resolved the issue.

I will update this thread in future if anything changes.

thanks.

[JNoSol]

My ECL came on at 10k, due to a minor vacuum leak. It comes on and off. After the dealer replaced the vacuum hose, not more ECL since. Good luck!

[lindros2]

Same thing as OP and others. Two occurrences of ECL, about 2 months apart.

Replaced evap valve or DMTL pump (whatever it's called).

(then my headlamp control module went south... can't win...)

[faz]

Just an update: after replacing the DMTL pump, the check engine light has not come on yet, and all seems to be working fine.

Doing a Google search on DMTL, it seems like there are many similar issues reported in various BMW forums for various BMW models.

FYI, in one of the posts on another site that I came across in my search on DMTL pump, someone had posted the following on what DMTL does: (I am not sure how correct it is, I am just copy/pasting it here as general info)

"This is how I understand the system to work. The DMTL (Diagnostic Module Tank Leakage) pump tests the fuel tank and fueling components for leaks by slightly pressurizing the fuel tank and evaporative components. The DMTL pump contains an integral DC motor which is activated directly by the ECM which then monitors the pump motor operating current as the measurement for detecting leaks. The fault is set when pump amperage is above 40ma for 10 seconds, and seen for at least 4 drive cycles."

[iwinit]

I noticed the Check Engine Light in my car last Thursday when my gas tank was 80% empty. I filled the gas tank full and tightened the cap all the way. Then I drove the car for the next 3 days with the CEL on. This morning when I started my car, CEL was finally gone ! So, it was indeed related to the gas cap. I always tighten the gas cap to the point that I hear a click. But it looks like not enough. We have to tighten the cap all the way so it can't be tightened any further.

[iwinit]

Well, the check engine light came back on 2 days later. I took it in. The catalytic converter has fault and needs to be replaced. It will take 2 weeks to get the parts. My car has less than 8000 miles on it. I can't believe the cat needs to be replaced already. That is very disturbing. I will definitely sell it before warranty expires.

[Giantdubrx]

I have a 2011 535i as well and the check engine light has come up for the third time yesterday, (first last year, 2nd in August) 2k after the 2nd incident. Car has 28.5k miles.....great car when not in the shop. btw, off topic, had pull to the right issue finally fix in June, took them 2 weeks to figure that one out and ive fought over fading numerals on the central console a year into ownership as well.....again, love the car when its not in the shop

[TZ]

Originally Posted by faz

Just an update: after replacing the DMTL pump, the check engine light has not come on yet, and all seems to be working fine.

Doing a Google search on DMTL, it seems like there are many similar issues reported in various BMW forums for various BMW models.

FYI, in one of the posts on another site that I came across in my search on DMTL pump, someone had posted the following on what DMTL does: (I am not sure how correct it is, I am just copy/pasting it here as general info)

"This is how I understand the system to work. The DMTL (Diagnostic Module Tank Leakage) pump tests the fuel tank and fueling components for leaks by slightly pressurizing the fuel tank and evaporative components. The DMTL pump contains an integral DC motor which is activated directly by the ECM which then monitors the pump motor operating current as the measurement for detecting leaks. The fault is set when pump amperage is above 40ma for 10 seconds, and seen for at least 4 drive cycles."

Pick up this old thread.
Recently I got a CPO 2011 535iX. Yesterday the check engine light came on and threw a P0456 code on OBD scanner. I did some search and came cross this thread that seems to be similar issue. I took the car in service today. after 2 hrs wait. They told me the comupter triggered a fault alarm and they reprogrammed the computer. Does this sound right? I wonder how's your fix so far? Thx.

[493263]

Originally Posted by TZ693

Pick up this old thread.
Recently I got a CPO 2011 535iX. Yesterday the check engine light came on and threw a P0456 code on OBD scanner. I did some search and came cross this thread that seems to be similar issue. I took ithe car in service today. after 2 hrs wait. They told me the comupter triggered a fault alarm and they reprogrammed the computer. Does this sound right? I wonder how's your fix so far? Thx.

Sometimes it does trigger a false alarm so I wouldn't worry about it until it trips again. If it does, then it's either you got a leak, bad sensor or your ECU needs to be replaced. Demand a fix since you're covered.

[TZ]

Thanks. Crossing my fingers....
Here is the quote from the service report.
"
FC: 1613051200
PART#:
COUNT:
CLAIM TYPE:
AUTH CODE:

38306
verified complaint check engine on ..
hooked up battery charger performeq short test fault 190302 fuel
tank ventilation system and purge_air §ystem miGro leak leakage larger
than 0.5mm
ran dw punch for performing test plan
as per test plan diag code d1330_bOOOOOOO_Ol_901 dmtl system is ok
"

[Chuck W.]

I just got the P0456 code. Thanks you all for starting and adding to this post. It gives me some direction to go in. At 60,016 miles this is the first check engine code I have gotten. What a great car. I'll post my finding!

[TZ]

In my case, it tuned out to be DMTL module as well. The car has been great after the fix.

[Chuck W.]

Originally Posted by TZ

In my case, it tuned out to be DMTL module as well. The care has been great after the fix.

After looking at past postings I think the DMTL is a good bet. I gassed the car up and reset the check engine light. We'll see how long it last for. The DMTL is pretty easy to get to behind a rear wheel liner. Love this forum!