Arrie

The plugs cost about $13.50 / piece. I needed 8 of them, bought from Advance Autoparts.


For the job I needed a extension spark plug socket as the plugs are in a about 5" deep hole. To get to the plugs the air box on top of the engine needs to be removed.


I used air compressor to blow the engine top clean and then each hole where the plug is before removing the plug. The coil naturally has to be removed before getting to each plug.


For tightening I used about 18 lb ft torque with a small amount of antiseize on the thread. The manual calls for 20 - 25 Nm.


Easy job.

thefisch

Thanks Arrie. My dealer quoted me $600 for changing the plugs on my E550. What a rip. Local indys quoted about $250-275 for the same job which isn't too bad if your not inclined to attempt this yourself.

Either way you saved yourself some money.

Arrie

SIX HUNDRED BUCKS!!!


What a rip off.


I used about 2 1/2 hours doing the job as I made sure to check my torque wrench setting after each plug I fastened. There is no way this job takes longer that one hour at a Mercedes shop where they have all the correct tools at hand.


I have an extension plug wrench 12" long and it is a bit too long for the last plugs on each side as it comes very close to the heat shield around the engine, which is not that bad itself but on the driver's side an extra problem is the fuel line that is right where the end of my wrench was. This caused some extra time on the job. I would get a shorter plug wrench for this job.


It may look a big job when you open the hood and the whole engine is covered with the air box. That air box comes off straight up after pushing the metal wire retainer out right at the middle between the box and the fire wall. The air intake is right there. After the air box is removed everything is exposed. Each plug has a coil on top of it fastened with two screws that require having the torx key.


I had all tools I needed for the job as I used to fix my cars so I did not need to get any tools at all. But I would get the shorter plug wrench if I did this job again.

thefisch

Sounds like the indy price I got was fair based on the time you thought it would take plus the parts. After I found out what the dealer wanted I think I even asked if there was more involved in that repair for them like timing adjustments, tune up, etc. SA told me it was just the plugs but that it was a very involved process. I guess he was referring to removing the engine cover. They probably can't justify changing the plugs for $250 when that's what they charge for a service A.

Arrie

Your indy quote sounds very reasonable.

Removing that engine cover is very easy. You take off the front part first simply lifting it up at front edge first and then the back edge from the main part. Then you disconnect the air intake hoses from the connectors that are attached to the front and the small hose running to the EGR valve (I think?). After this you push the steel wire retainer away from the air box right in the middle between the box and the fire wall. After this the box can be lifted up.

The air box is held in place by four big spring clips and the rubber seal where it connects to the engine air intake hole and that steel wire retainer.

It is a good idea to cover the air intake hole while the air box is off.

This engine cover / air box comes off the engine in less than one minute after you know how to do it. It also goes back in almost the same short time. There is no way to justify the $600 cost for the plug change. Total rip off.

cx876

if you can tighten a bolt you can change your own spark plugs, simple as that,
I done it twice on my SLK and it should not take more than a hour for the job,
and there're tons of DIY post online for the M272 engine, can't get any easier than that.

C230Brit

Thanks for the write up about the Spark Plugs - changed mine today. It was good to already have the correct tools on hand thanks to this guide.

Overall, took me about 45 minutes I would say.

I noticed that my OEM plugs were labeled with both NGK and the Meredes logo. I swapped them out for NGK's.

TYUS

=YES SIR; ITS TRUE, THE 2006 C280 W203 THAT I USED TO OWN HAD PLUGS LABELED WITH MB. THE PLUGS APPEARED TO BE MANUFACTURED BY ONE OF THE ASIAN COMPANIES THOOGH.

Arrie

So, what's the point?


If you had the plugs with MB logo on them then get the matching plugs.


If it happens to be that you cannot find them any more then I suggest to find NGK plugs for your vehicle,.

jahquan3

This is what dealer told me as well. He also said the original ignition coils have a star on them also. I didn't actually see them though.

Luddyludwick

Thanks for posting here, and I'll shamelessly bump this three year old thread. Was going to do mine today, but have a couple sick kids.

My E350 wagon is only getting about 15 city/ 20 highway (less when my wife is driving, unfortunately), so I thought I'd better check records (we just bought the car). It was dealer serviced its entire life, and there's no mention of a plug change, and since we're at 125k, I figured it was time. I don't think the MAF has been cleaned, either, so I'm planning on doing these two jobs at the same time.

If anyone prefers a video link for changing plugs on the M272 engine, here ya go!