biswassb

I have a 2014 GLK250 (first owner). In July 2019, a check engine light came on and it was code P2002 which is DPF malfunction. I tried every possible way including DPF cleaning to correct it and spend a couple of thousand dollars. Nothing worked! Then in August I went to our Mercedes dealer and they check the car at a cost $600 only to tell me that the DPF needs to be replaced. They warned me it might take many many months to get a reconditioned DPF from Germany. They also urged that it may be better to trade the car in for a new Mercedes without such a problem. In the mean time I received numerous offers from Mercedes to trade my car in for a GLC or GLE. I am not sure whether there is a connection of these offers with my car's DPF problem. It certainly looks like Mercedes is trying to withdraw these diesel GLKs from the US market for reason unbeknownst to me. I also have a 1999 ML430 and I never got an offer from Mercedes to trade it in for 20 years. I wonder what gives? Because of this DPF disability of my car, it did not pass NJ inspection even though this car is perfectly fine in all other aspects. And thus, very soon I will not be able to drive this car and have to buy another car. Certainly, it is not going to be a Mercedes. I am very distressed about this.

bugelrex

What was the trade in offer. They might be hedging their bets against a successful diesel emissions lawsuit...

Btw. Have not received any offers for my glk250. Also in NJ

andreigbs

Sounds like your MB stealership is only knowledgeable about selling cars, not so much on proper diagnostics and repairs. I would steer clear of them in the future.

Assuming it IS the DPF, and nothing else (like a sensor), it should be possible to have the DPF physically removed and cleaned. Many big rig truck repair shops are equipped for this job, albeit they might not be too comfortable performing surgery on your Benz. It's up to you if you want to try it and up to them to agree to do it. If this also fails, or the job is too expensive or just not worth it to you, I would consider resetting the CEL and trading it in before it pops on again.

Since your state requires emissions testing, you likely won't be able to renew your registration with a failed inspection. Your state may have some kind of waiver program where if you spent enough on repairs but still couldn't get it to pass they might give you this waiver. At least that's how my old state (Georgia) would proceed. In any case, replacing the DPF at your MB stealer will be expensive and there is no guarantee the replacement will work flawlessly. These Bluetecs are too complicated and super expensive headaches when they go wrong.

Good luck.

biswassb

Well, Past Monday (11-11), we noticed while driving to work that CEL is totally off and all on its own. We do not know why. We decided we will drive to work (120 miles round trip) so that the system has a chance to cycle and see whether it stays off . Unfortunately on the way back it came on again. So we could not get it inspected. Then yesterday (11-14) on the way to our long journey to work, we noticed the CEL is off again and we decided to do the same meaning drive 120 mile round trip to work. This time the CEL did not come back on. Realizing that the system probably cycled after the trip, we drove the car to our nearest NJ MVA inspection this morning and guess what, it passed inspection and I got two years. Hope it lasts. Incidentally, I also got a brand new offer from Mercedes for trade in (attached). BTW, Mercedes Wilmington is the worst Mercedes dealer around. I believe they created the DPF problem when I took it there in July and I refused numerous services they offered to do.

biswassb

GLK250 is a great car. It gives me 30-35 MPG. We have a 120 mile round-trip drive to work everyday and we do it with 4 gallons per day. We could do it because of this car. Car has 136,000 miles on it. Other cars will consume 8-10 gallons a day making it prohibitive not to mention pollution. We tried a variety of repairs that did not work immediately. Can't figure out what finally fixed the DPF and CEL. But I am very happy !!

andreigbs

That's a happy surprise that it cleared itself after a few cycles. Hopefully it stays off. There are additives you can run to help clean the DPF, such as LiquiMoly DPF products and even Lucas products like Diesel Deep Clean. These may also act as preventive measures to keep your DPF as clean as possible, and using them regularly may help extend your DPF service life.

Amazon sells both, I hope you do some research.

Happy motoring.

bugelrex

wow, 120 miles round trip. Diesel all the way in this case!

Gazwould

Same engine in a W204 C Class and it's even more smiles per gallon .

biswassb

I learnt a lot about diesel cars, and GLK250 during my DPF trouble. I am surprised how little information is available and Mercedes did not provide any information on how to take care of a diesel car. One of thing we observed is that the car's performance is interconnected with the DPF and CEL. After P2002 code came on, car was not driving smoothly. It was rough. When the CEL was going on and off, what we observed is that when CEL was ON car was running rough and when CEL was OFF car was running smooth. It could be that the DPF problem and code P2002 is an indicator of overall engine performance and DPF is probably a symptom.

I slowly realized that DPF clogging is not a real problem, it may be a manifestation of the overall engine health. And that is why Mercedes is reluctant in supplying new or reconditioned DPFs to customers. Dealerships probably know how to fix this problem without changing the DPF but they do not provide that fix to the consumers in order to make money. In my case, after my local mechanic could not solve the P2002 code problem, I took the GLK to the original dealer, Mercedes Fort Washington. I could tell that they were very wishy washy. They charged me $600+, told me that I need a reconditioned DPF for about 3000 but it may or may not solve the problem and some of the sensors (another few thousands) may also need to be replaced. The manager indicated that it is a rabbit hole and I will be better off trading it in. It was disappointing that they could not pinpoint the issue and gave me a totally hopeless and misleading view of this problem. They were simply trying to use the DPF problem to sell me another car and that too not a comparable car. Now I know that it was probably an engine issue that got slowly fixed with my mechanic's many attempts to repair.

If anyone having a DPF problem, it will be advisable to look at the overall engine performance in a holistic way rather than replacing the DPF. This car (other diesel cars) is not for those who drive locally shorter distance every day. It suits me very well probably because we drive at least 80 miles on freeways at 75-80 mph five days a week that should regenerate the DPF every time. Even my recent DPF problem popped up after five years and 135000 miles.

bugelrex

Curious, what is the best way to keep the 250 running well? Very long drives every few weeks? Driving it aggressively a few times? Keeping the tank full? No idea

andreigbs

Sometimes it’s the luck of the draw. In general, diesels don’t like short trips where they don’t get a chance to fully warm up and stretch their legs. They are built to run hard and serviced regularly. If it’s turbocharged, it needs to be run on full boost often; no pu$$yfooting around like an old lady.

They also need the proper oils and clean fuel. If equipped with DPFs, the type of oil and quality of fuel can greatly affect service life of the filter. A good hard highway run helps keep it clean, and as I said, there are additives you can use to help combustion be the cleanest it can be. That prolongs DPF life. But at some point, it may not be able to be cleaned (regen) anymore and if it’s plugged up, you’re going to have problems. It’s just a matter of time even though you can delay it with proper care.

People these days don’t keep cars for much past 100k miles, and that’s the period in life where these cars start to show problems. Others are unlucky and have these problems early on. The best advice for those considering or owning diesels is run them hard and often, and take care of all maintenance by the book; no skimping. I’ve had diesels last me over 300k miles that I’ve then sold to others. They just need the right care from the right owner.

biswassb

This is my first diesel car. I wanted it because diesel engines do not heat like a gasoline car and lasts lot longer at least in theory. In addition, Mercedes engineered a four cylinder turbo-charged engine partitioned into two two-cylinder engines in reality is a marvelous engineering. That could also be problem, because the second two-cylinder engine does not activate in this car until you get into like a freeway speed. After the DPF problem I found out about the general wisdom of driving it at high speed for a period of time. It suited me well. If you have no need to drive longer distance regularly it will be problematic and occasional long trips should help. Oil change frequently locally. I buy the desired oil MB filter and get a local shop do it. I add Peak BlueDef myself. In addition, quality of fuel is also a factor I think. I found our local NJ Phillips-Conoco diesel worked better in my car. There must be others equally good. But other than this problem, GLK250 is a fantastic car. It is a dream to drive. My first car was a 69' Mustang, second car 90 Ford explorer, third car 99 ML430 and GLK is my fourth. GLK drives more like a Mustang than a Ford explorer. In 5-6 years and 136K miles we had practically no issue other than this one.

andreigbs

Would you have some references for this? It almost sounds like you’re describing cylinder deactivation, which is not how the 2.1L OM651 operates.

biswassb

It must be there somewhere in Mercedes publications.

GLK Super Fan

I wish they sell C class with the diesel engine in Canada. i will definitely get one. I was able to get my glk to 4.8L/100km, not as good as yours, but GLK also weights little bit more and has air dynamic like a brick