[Used2335]

I've got 30k on my 07 335i and its completely stock. I recently noticed the "service engine soon" light, and I checked it with my generic OBD scanner and its coming up with P1447:

Diagnostic Module Tank Leakage (DM-TL) Pump Too High During Switching

I've searched and searched, and basically I've read that this can happen due to little things like not a tight enough gas cap, or overfilling the gas tank, etc. but I have reset my light and it comes back within a couple hundred miles.

I am just out of warranty, so would you guys recommend I just go out an buy a new DMTL Pump? I generally do small maintenance myself (seems like an easy job). Is there any other things I can try? Is there any way to repair the pump without having to get a whole new one? Thanks for your time!

[GMWNashville]

id do the dmtl pump...its easy to replaced its in the left rear of the car behind the wheel theres a plastic cover with a few 8mm screws...

[Used2335]

Thanks for the reply. I think its either got to be this, but I also ran across a thread somewhere else today that suggested my gas cap could be the culprit. Is there any way of telling whether I have a bad gas cap? How does your GAS CAP go BAD!? I think that's hilarious...

[Calhoun]

Had the SES light up on my '07 328 xi with 54k . Pulled code P1449 at Auto Zone, actually bought the BV Enthusiast cable, pulled the equivalent code, 2A17 - Diagnostic Module Pump Leakage (DMTL) Pump Current Too High. Replaced the DMTL which resolved the problem. The process took me about 20 minutes, very simple, you don't even have to raise the car. The BV tool is pretty slick, already used it to reset the CBS after an oil change.

[dassub]

Yeah when this happened on my car, they asked if I put the gas cap on correctly. Yes I did. Then, they reset the light and told me to drive around for a few days to see if it comes back. It did, and then they changed the DMTL pump under warranty.

[Used2335]

Originally Posted by Calhoun

Had the SES light up on my '07 328 xi with 54k . Pulled code P1449 at Auto Zone, actually bought the BV Enthusiast cable, pulled the equivalent code, 2A17 - Diagnostic Module Pump Leakage (DMTL) Pump Current Too High. Replaced the DMTL which resolved the problem. The process took me about 20 minutes, very simple, you don't even have to raise the car. The BV tool is pretty slick, already used it to reset the CBS after an oil change.

Thanks for your reply. I have the 2 door, do you think I'll still be able to reach that back panel without jacking up the car? That is the only thing holding me up from replacing the part.

[Calhoun]

I have a sedan, but the Bentley manual doesn't seem to differentiate between the 2 body styles, so my guess is that access would be very similar, or the same. You should be able to tell very quickly by looking for a relatively small underbody cover on the rear passenger side, about 24" square. Remove it, and look for the black (plastic) charcoal cansister about the size of a loaf of bread, the DMTL is one the same end where the lines (1 electrical) connect. The connector for the electrical cable is pretty easy to understand, the connectors on the other lines were a little less intuitive (for me anyway). I squeezed inward on the ribbed sections while pulling straight outward, they came off after some modest tugging. On my vehicle the largest one took the most pulling force to remove, and then the most pushing force to reinsert. I was careful to listen for all the lines to 'click' into place to be sure I got everything back together, and wasn't creating any leaks. My recommendation to you is to buy the Bentley manual, it's an indespensable reference tool.

[GMWNashville]

the only difference between the cars is between the 335 and 328...328 is passenger side 335 is drivers side and i think the verts are at a diff location but i forget off hand...

[Used2335]

Originally Posted by volkswackin

the only difference between the cars is between the 335 and 328...328 is passenger side 335 is drivers side and i think the verts are at a diff location but i forget off hand...

You were right, it was on the drivers side, and it was fairly easy to get in to. Just for the heck of it, I took the pump, and blew out the inside with an air compressor and put it back on. After clearing the code I've been CEL clear for probably 500 miles. Hopefully this continues! Thanks for all the help.

Sam

***************UPDATE******************** September 13, 2011
I am still CEL free from this. Just something you guys might want to try before shelling out the $$$ on a DMTL pump! I drove around like a day without putting back on the cover just to make access easy, but everything is great!

[d3l0n]

Originally Posted by Samcrac

You were right, it was on the drivers side, and it was fairly easy to get in to. Just for the heck of it, I took the pump, and blew out the inside with an air compressor and put it back on. After clearing the code I've been CEL clear for probably 500 miles. Hopefully this continues! Thanks for all the help.

Sam

***************UPDATE******************** September 13, 2011
I am still CEL free from this. Just something you guys might want to try before shelling out the $$$ on a DMTL pump! I drove around like a day without putting back on the cover just to make access easy, but everything is great!

Nice. I have a 330i and would like to try this. I replaced my gas cap and it came back after approximately 150+ miles. Is there a DIY for this? Or any pics for guidance? Never did this before. Don't even know what it looks like. I assume I can follow a 328i doc as well?

[Saintor]

Originally Posted by Used2335

You were right, it was on the drivers side, and it was fairly easy to get in to. Just for the heck of it, I took the pump, and blew out the inside with an air compressor and put it back on. After clearing the code I've been CEL clear for probably 500 miles. Hopefully this continues! Thanks for all the help.

Sam

***************UPDATE******************** September 13, 2011
I am still CEL free from this. Just something you guys might want to try before shelling out the $$$ on a DMTL pump! I drove around like a day without putting back on the cover just to make access easy, but everything is great!

Was the DMTL pump something that you can remove without having to mess with all the car gas?

[Used2335]

Originally Posted by Saintor

Was the DMTL pump something that you can remove without having to mess with all the car gas?

Yeah. I'm not mechanically oriented at all and I took it right out. This is one of the only DIY sort of things I preformed with having everything go the right way the first time!

Oh, and I no longer have my 335, but I put close to 10k miles on the car after taking the air compressor to the DMTL pump and the light never came back. While YMMV, I would suggest it, I remember the part wasn't cheap when I inquired about replacing it.

[bm6w]

Threw all the codes for DMTL. Replaced pump and that didn't fix it..same codes. I checked the wiring for the sensor going into the pump and its all fine. I guess my last thing to do is replace gas cap?

[GMWNashville]

What codes exactly did it throw? Pump current faults or leak faults? If leak faults it can be a fuel cap, purge valve, leaking o-ring, and a handful of other things though those are most common.

[lypkkj]

My car has thrown the P1447 code as well.

My question is if I remedy the source of the problem will the light go off on its own and when or do the codes need to be cleared by some means? If the codes need to be cleared is there a simple and cheap way to do it? Thoughts?

[F22_Raptor]

Originally Posted by lypkkj

] If the codes need to be cleared is there a simple and cheap way to do it? Thoughts?

I just got this code in addition to a P1449 code.

Im gonna try buying a Guaranteed to Pass and see if it works. (made my CRC)
Then im gonna disconnect the battery to try clearing the code. For some reason my OBD2 scanner isn't able to delete it.

[WIREZ71]

Newbie here.. to wake up this thread again.

I recently purchased a 2011 328i from a one owner. 74K miles. Put about 1200 miles on it and the SE light comes on. Went to local Advance Auto.. P1447. Diagnostic Module Tank Leakage (DM-TL) Pump Too High During Switching.

K. I have read this thread several times. I just yesterday installed a NEW Bosch pump. $69. I have read a couple of post about how to reset the light. I have disconnected the battery cables... Touched the cables together. Put them back. The SE light is still ON.

What did I do wrong? Any thoughts?? Thank you!

[WIREZ71]

bump

[ToniQ]

This link shows you how to change the DTML pump: https://www.pelicanparts.com/BMW/tec..._Replacing.htm

[ToniQ]

I meant to add that this is for a 2011 335is. I am sure other models and years probably use the same procedure: https://www.pelicanparts.com/BMW/tec..._Replacing.htm

[2013328iNC]

Got the same codes but, before I pull the pump, I noticed that there was no pressure when I opened the gas cap. Ignorant question... but does this indicate anything helpful? Thanks.