NYCGLK

I just rolled over 63k and realized I needed to do plugs.
I ordered 6 bosch plugs from FCP euro in CT for $49.44. Changing plugs was easier than the oil change. 2 of us did both (plugs and oil change) in a bit over an hour.
I actually called dealer after the fact to see what this would cost. Dealer wants 367 plus tax, which is an incredible rip off.

Quick steps:
- Remove the air filter cover
- Remove coilpack bolts (2 per coil pack - you need T30 torx iirc)
- Unplug coilpacks - leave them such that you can figure out the order they go back in or just do one at a time.
- Replace sprakplugs - they came out easy and they looked perfectly fine.
- Make sure not to cross thread the new plugs. I didn't use any anti-seize.
- Plug the coilpacks back in, put bolts back in, put airfilter box back.
- Have a beer you are done.

Sorry no pics, but you can google for E350 W212 DIYs.

spyked

Your sig doesn't say what year...are you on the M276 engine or the earlier range?

Thanks!

Actually, never mind, I see your pic.

NYCGLK

M272
2010-2012

lyonkster

Thanks for motivating me, I'll do this project next weekend. When googling GLK plug replacement, I saw all sorts of references to two plugs per cylinder, I assume there is only one in the 2010-12 GLK's?

lyonkster

Here are a few photos of what's involved. I'd say this is one of the easiest plug replacements I have done in years (40 minutes total including photos, compared to about 4 hours on my minivan where half the motor top end needs to come apart). I hardly dove into my toolbox and didn't even get my gloves dirty. Fun!

First remove the front plastic piece by pulling up:



Then disconnect the one hose in the middle and two large ducts on each side of the air box:



Undo the clip on the back of the airbox, and pull up to remove. Here you can see the attach clips on the bottom of the airbox that you need to disengage and will need to reengage:



Now you can see the two timing covers with the coil packs. Passenger side:



Driver side. If only the minivan was so accessible!



Each coil pack is held by two T30 torx screws:



Remove the screws, and pull up on the coil pack to remove. Here is what it looks like once out:



Here is the spark plug, deep in the timing cover:



Remove it with a 5/8" spark plug socket:



Here are all the coil packs removed:



Here is an old plug next to new. The old ones had more wear than I expected:



These are the plugs I used, Bosch YR7MPP33:



I used some dielectric grease on each ceramic electrode to make it easier to remove the coil packs next time:



I torqued each spark plug to 23 Nm, and each coil pack screw to 9 Nm. Pop on the airbox (make sure all corners seat properly), connect ducts/hoses/clips, and call it a day. Too early in the morning for a beer .

NYCGLK

Glad you tackled it. Good pics.

PHML

What brand was the OEM spark plugs?

lyonkster

Bosch.

h00pak

Our local Mechanic wanted more than $500. That just made me angry.

jorgevg73

I was quoted almost $900 for spark plugs for my 2015 GLK 350 4MATIC. Is this armed robbery?

formerjeepguy

In a word, yes. Shop around and check the dealer website for service deals/coupons. I just had the plugs done in my 2015 with the m276 engine for $580 including a loaner and car wash. I used a 10% off coupon.

NYCGLK

I just did plugs on 2014 E-350...definitely more PITA than M272. I think dealer quote was 600 or 800, something stupid. But I would actually rate this more difficult than brakes, because it's a maze of wires and hoses you are dealing with when taking entire intake manifold. Good time to replace the air filter if you have done it.
If you DIY, get new intake manifold gaskets, make sure all vacuum hoses are plugged back. You will also need skinny E8 (1/4 inch) and the new 12 point spark plug socket.
Google for PDF of DIY there is a good one out there with a tip on pulling coils off the plugs using a string, we arrived at the same for 2 coils on driver side where access gets dodgy due to ECU brackets and wires.

adamant118

driver side of the motor Question, how did you get to this plugs on a driver side? Six-cylinder, correct

formerjeepguy

He has the m272 engine. Your 2015 has the m276. Different beast.

adamant118

i have a 2015 glk 350 . i need to get to coil pack 4..

drewcwsj

For my '13 I just got quoted $660 by the dealer and $550 by an indy. Looked at the M276 procedure and it looks complicated.

chassis

M276 spark plugs are not too bad, but it takes time. Approx 1hour for the passenger side, 2-2.5 hrs for the driver's side. The driver's side has the ECU, ECU bracket, large ECU harness, PCV/vacuum lines and the steering shaft.

drewcwsj

A 4 hour job with lots of warnings is just too much risk/return for me to attempt. I will wait for a deal at the dealer - which they offer every few months or find a cheaper indy.