pkov8

GLK250 MY2014, 29,000mi

Symptoms: CEL on with 10 Remaining AdBlue starts. Code PB2AA with simple scanner. DEF reservoir was >75% full and topping off had no effect on issue.

Solution: Took to MB dealer for emissions warranty repair (8yr/80,000mi). Diagnosed as clogged lines by tech. Nozzle and exhaust ports were cleaned which resolved the issue.

Feel like I got off easy after reading about NOx sensor and AdBlue system components going bad... Hope this helps others out there with the same issue.

andreigbs

29K miles? In 6+ years?? Methinks you need to drive more. These modern diesels don't like short trips, they need long highway pulls to get hot and clean stuff out.

pkov8

Picked it up 3 months ago with 26k, so working on that! Kind of tough being quarantined though...

andreigbs

Agreed that the "safer at home" orders makes for little driving. Still, amazed that you found such a low-mileage specimen. If it makes you feel any better, ours has a little over 122k miles and runs like a champ still. Until recently my better half was racking up 600 miles per week.

I assume you know about the proper MB specs for oil, and I would highly encourage you to stick with the approved ones. Ours has done all its miles only on approved fluids and I have no issues to report.

I'd also suggest you plan on new tires soon, because if those are the originals they're probably close to getting dry-rotted. If/when you do, think about ditching the run-flats and you might be amazed how comfortable and well-handling vehicle it can be (I'd personally recommend Michelin Premier LTX or equivalent).

I would also replace the fuel filter and air filter, if they're original. 6+ years is long enough, and they're easy to change.

In any event, welcome, good luck and happy motoring, once things get back to normal (whatever that will be...)

pkov8

Definitely feels like I lucked out. Single owner and entire life spent in San Diego, with lots of factory upgrades to boot. Bought at MB dealership so they performed re-sell inspection, service, and some body work. Slightly out of CPO range, unfortunately, but for <50% off MSRP, I'm ok with that!

Thanks for all of the tips! I performed an oil change after driving 2k miles and sent the used oil to Blackstone which came back with a clean profile. I used Motul 8100 X-Clean EFE 5W-30 Synthetic oil (229.52). Replaced oil filter and O-rings of course. Planning on regularly changing the oil after 6k miles instead of 10k. Thoughts on this?

I swapped out the air filter and cabin filter already. A new fuel filter is sitting in its box, so I'll get to that next. Poly-V belt change and new pads/rotors are also on my list. Good call on inspecting the tires further and considering a cushier ride.

Have you ever had your fuel injectors out? Was considering changing the seals as preventative maintenance, maybe at 50k.

Appreciate it and looking forward to the first real road trip, hopefully sooner than later.

andreigbs

Sounds like you’re on top of things, which will serve you well in your ownership. If you don’t have one already, invest in a decent scan tool that’s MB specific. You’ll be glad you did.

On oil change: it’s up to you, but with the quality of diesel fuel and synthetic oils we have available, there’s no reason not to go the full 10k miles. In fact, I’ve often gone over by several thousand miles to no ill effects. But 10k is a nice round number.

On the poly-v belt change: I’d run it as is, unless you can visually determine there are cracks in it. FWIW, I’m on the original at 122k... it’s planned for at 130k.

On the fuel injectors: if you get curious you can read some of my early posts here (long story) but suffice to say yes, I’ve had fuel injectors replaced around 52k miles by the MB dealer. They did not do an excellent job and I’ve never been back since. One of the four injector seals is leaking juuust slightly enough to turn diesel fuel into black little lumps of shiny bitumen. If left unchecked it will turn into the infamous “Bluetec black death.” Look that up when you have time, for *****s and giggles.

Other than that, I’d say plan on a driveline flush around 60k miles (transfer case, tranny, front and rear diffs) and you should have zero issues with the driveline. Good on you for proactively changing other filters when you got it; I do the same on cars new to me.

What options is yours equipped with?

pkov8

I’ll schedule those other maintenance items. Thanks! Here’s what mine came with. Only extra thing I wish it had is adaptive cruise control.

andreigbs

Nicely equipped. I envy the leather interior, ours has the MB-tex.

The only other differences is ours has the AMG pkg and adaptive xenons. Enjoy the car, it’s quite a beast.