gkgeiger

My Ml250BT has been at the local (selling) dealer for several days now and they won't do anything. Here's the story: I was 400 miles from home visiting friends when my SUV lost power and and wouldn't shift above 4th gear. After a couple of miles the Engine light came on. It was late Friday and all dealers were closed. Sat. morning I called RA and they flatbed-ed it to Winston Salem NC. On Monday they checked the car and said it had a DPF trouble code which needed replaced. They didn't have one, said it would take a week to get. They suggested that they clear the code, take a test drive and see what happens. That went well so they said to drive it home and take to my local dealer. The trip home went well. I took it to the dealer the next day, gave them the paperwork from WS. They called me a couple days later and said they couldn't duplicate the problem, no codes stored. So they won't do anything. I don't have my paper work from WS so I don't know the trouble code. It was something like P2543 but not sure. Are there more then one DPF trouble codes, and is there someplace I can find what the factory shop manual says is the proper correction for such codes. I'm a retired GM service mgr. and would like as much info as I can get before I contact MBUSA. Oh, I have 43k miles and will run out of warranty when I'm in FL. for the winter. Thanks in advance for your help.

kajtek1

Dealer keep records in central database, so your dealer should have no problem to find the codes the other dealer. recorded.
DPF for 651 engines are not available in USA. I am waiting 3rd month for a rebuild one from Germany.

gkgeiger

It took nearly 100 views before someone responded. Thank you. I was in contact with both involved dealers today and I'm hoping that something is resolved. Is your vehicle drivable?

kombifan

Anthony Porta

Was there a RPM limit as well as a torque limit?


Maybe they randomly fail but I dont see how. Have you used an diesel with more then 5% bio diesel?

Sometimes there is an issue with getting it up to temp to make a "burn" of the soot. Often a teach-in will resolve the issue, how many miles have you driven? If there is an issue for me it came up between 50-500 miles. Eventually though, it WILL fail, 100%, guaranteed.

gkgeiger

I can't answer that, just no power. To my knowledge no Bio. The car has 43k and I just finished a 400 mile trip.

gkgeiger

I just got a call from MB Akron, they called MBUSA and gave them the info and was told not to replace the DPF. He also said it is warranted for 8yrs and 80k miles. My concern is when and where will this happen next?

400ixl

Extremely rare for a DPF itself to fail. It is usually some other issue which is stopping the car from doing an automatic re-gen which means it fills up. A full DPF can send it into limp mode, but doesn't stop you changing gears, just being able to rev very high in each gear if in limp mode.

You need to understand the code that came up as it is more likely for one of the sensors. Codes are often logged even if the MIL light hasn't come on.

Get them to read off the DPF figures through STAR and that will tell you both the soot % and the ash% which gives you a guide as to whether there is an imminent issue with it being close to full. If it is, get them to force a regen to get it down. If STAR can't force it then it will give the codes as to why it can't. Those will be what needs resolving.

All 101 stuff that a decent mechanic would know, unfortunately many main dealers have technicians who only know how to follow the book,

gkgeiger

Codes: P246364 & P246385, I'm sure if either one were for a sensor, it would have been replaced by one of the dealers involved.

400ixl

And what are the percentages of the DPF. Seen this where the DPF sensor is faulty and reading the wrong voltage to what it should have and the DPF soot % was actually fine.

Other times it can be the sensor hasn't thrown a fault in the system, but is still faulty, DPF's don't just fill up and require replacing for no reason. There is a cause as to why the regen has not happened, that is what they need to be working out. They need to use other information and take live readings of all of the sensors to look for anomalies.

kajtek1

Per my SA the filters are wearables with 80 k miles life expectancy.
Mine (per records) was replaced at 120k, and now at 183 k is so clog, that ultrasonic cleaning did not restore it.
In my case the issue could be that I had MAF and Ox sensor failures one behind the other, so for some time DPF could get extra sot, but the $3000 part did not make 2 months delivery deadline and now I am entering month 4 when I can't drive the car.
It is driveable around the block, but when I took it for longer drive - it went in strong limp what I think was 2nd gear. Not going to force it.

gkgeiger

As a retired GM service director, I can tell you that these people don't like customers telling them how to fix their cars. I'm at their mercy and will just have to take my chances. Thanks for all the replies, originally I just wanted to see if anyone could tell me what the fault codes were and what the factory recommended correction was. I will be picking the car up tomorrow.

gkgeiger

I picked up my car this morning and I'm disturbed that two dealers are telling me two different tales. If there is an MB service guy on here, please PM me so I can ask a question. Anything you say will be confidential and I will not use your or your dealers name. Thanks,.

kombifan

gkgeiger

Very interesting read. I wonder if any of the weaknesses of the 642 were corrected in the 651 version? I don't hear a lot about the 2.1L engine. I have contacted my service mgr. to see if I can get a copy of the bulletin mentioned in the article. Mercedes-Benz document; SI00.20-D-0029A, dated 5.4.12

a64armt

gkgeiger

You would be doing me a big favor if you would give me the trouble code that led to the replacement of the DPF. Thanks in advance.

a64armt

kombifan

gkgeiger

I just read your thread and I agree that if there wasn't a trouble code listed on your invoice, something is wrong. In that thread it sounds like you hadn't rec'd the DPF but you must have just got it.

400ixl

The DPF is a wearable item, but from an ash content perspective that is in the 200,000 mile plus range. Europe has a far more consumption of diesels and DPF failures needing replacing at sub galactic mileage is very very low as a percentage of cars sold. The times they do need replacing is due to an unaddressed issue causing the system not to do regeneration which clog them up to the point they cannot even be manually cleaned (some dealers condemn them without even doing this) or partial regens mean they fill up with ash.

Has the dealer done a forced regen and then supplied the soot % and ash % readings from STAR. These will give you a good view of the condition of the DPF itself.

peter2772000

Maybe you need to perform this aggravated DPF block/unblock procedure;

kajtek1

The OM651 engines are rare in USA, becouse they made it here only in last 4 years, in the time of bad wrap, while they run on European roads for about 10 years.
The only predicted worry about them is timing chain.
I finally had some good luck with my DPF >>> my iCarsoft has generic regeneration program, who is pretty chaotic and unrealistic as it calls for keeping 2000-3000 rpm while not exceeding 50 kph.
So I took it on back streets and playing with manual shifting kept the range to best possible. Even the scanner talks about 45 minutes, I drove like that for about 5 miles and the program says the adaptation is completed.
My level of particles went from 300 down to 16. Still will have to take it for longer drive to see if it is holding the parameters, but so far I am happy camper.

DC-BENZ

I haven't talked about this on here yet but I had a DPF and limp mode issue. After exhaustive research (mostly on Sprinter and Ford Diesel sites) I stumbled across an exhaust sensor being the issue. The cost was around $60 and at the rear center(near firewall) in the engine bay. I haven't said much about it because it's only been a few thousand miles since.

Also, I learned that I need to activate the DPF cleaning manually so I bought an Autel reader that can do so. Part of the code read was that I had "too many incomplete DPF cleaning cycles". My rush hour drives do not allow the cycle to be completed even though my drives are around 30 miles each way when I drive..

gkgeiger