Guppies838

Wow I look at this 2012 C350 4M looks like changing the spark plugs specially on the driver side is pretty hard.
Anyone have a video or how too. Can't find on yourtube. 2010 is easy but not this 2012

alecmascot

It would be a big help if you would post your vin, or at least the engine model number.

gamma300C

error

JettaRed

iTrader: (1)

I was thinking the same. When did Mercedes start using the M276 engine? Spark plug change on that engine is quite involved. The plugs have to go in at a precise torque to ensure proper clocking (orientation) to the fuel injectors. Then, you have the whole intake thing to deal with.

Adi-Benz

Haven't seen the process for the M276 but on the M272 it's arguably the easiest spark plug change I've ever done (did them recently).

DeTh

For 2013 + M276 DE35 you have to pull the intake manifold per the TSB for spark plug change. $700+ at a dealer. I'm doing my 60k soon, going to attempt myself

Odd Piggy

Here’s a video of doing it from another MB site.

https://www.benzworld.org/threads/vi...-m276.3044229/

Some say the manifold does not need to be removed. This is on an E-Class so not certain if it applies directly to C-Class cars. There was a step by step in the SLK forum, but the pics seem to be no longer available.

One note: removal and installation of the plugs on M276 requires a special 12 point thin wall socket like Assenmacher SP1412.

Guppies838

Don't I need a 16mm for 2010 C350 4M for spark plug socket

Odd Piggy

2010 C350 4m with M272.961 uses 16mm plug socket
2012 C350 4m with M276.957 uses 14mm 12 point plug socket

Canada cars are sometimes different from US. Please post your VIN or check lastvin.com for engine type.

JettaRed

iTrader: (1)

Here's the parts you need for the M276 engine.

https://www.fcpeuro.com/products/mer...sch-0041598103

JettaRed

iTrader: (1)

Guppies838

Thanks ! I am in Canada I have to find someone I know live at state to get me the parts. The shipping cost is crazy

DeTh

Thanks for the info guys. It looks like a major PITA compared to other motors
Guess we'll see how it goes in a month and a halfs time. Might document it, we'll see. I'd already ordered the FCP Euro kit without the 12pt socket as I'm pretty sure I have one (I was planning on doing it over spring break but plans changed). If I can change the plugs without pulling the intake manifold and replacing the plenum gaskets then that would certainly save me some time. Especially because I'm doing the 722.9 transmission fluid change aswell

JettaRed

iTrader: (1)

The socket that comes with the kit it thin-walled to fit in the spark plug well. You may wish you had it when the time comes.

I've done this job and it really is involved. If you don't have time to do it right, what makes you think you have time to do it over? Don't take short cuts on this one. And get a good torque wrench. You want to torque to exactly 23 Nm as prescribed. A digital torque wrench may be your best option.

The first time around, this is costing more than you probably planned for. But having the right tools and following the procedures makes the job easier in the end. And the good thing about FCP is that you we never need to buy the kit again. (Actually, you do buy it a second time, but you send the old parts back and they refund the price of the new kit.)

DeTh

Yup, I’m familiar with FCPEuro and their refund policy. I’ve got a craftsman digital torque wrench, I believe it’ll do the job fine. I have another thin walled socket that I’ve used for spark plugs on other cars in the past. Appreciate the advice.

JettaRed

iTrader: (1)

I think you're better prepared than most. Piece of cake!

capt_paul

c350 has a m276. Plenty of YouTube videos on how to as well as instructions in these forums

Guppies838

I own 2 C350 here. 2010 and 2012. I have time to doing it. I just to mske sure what to do before I start. I finially see an youtube by FCP very detail.
I have torue wrench here and I just need to get the spark plug socket. I am sure the 14mm is for 2012 and 16mm for 2010 C350.

Thanks !