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Hi Folks,
I'm a new owner of a 2016 C350e with 23K miles on it. (Same engine as the W205 C300)
While the electric drive is amazingly smooth, and the engine runs well...with mostly seamless transitioning in and out of gas/electric, the idle seems rough and on occasion the motor kicks in a bit abruptly.
I've read the TSB where MB changed their recommended spark plug replacement interval now to 30K (vs 46K). One previous owner at 55K complained that his plug broke and damaged the engine, requiring replacement .
I understand that the multi-spark plugs are actually used far more intensely (~10X) than traditional plugs, and am wondering if others here have seem premature wear of the OEM plugs. Ive also noticed that MB changed the plug part number from the NGK 90654/0041597003 to the new NGK 2701590700.
Bottom line for me is that I am thinking to replace the plugs at 23K, with the new OEM part...and wanted to hear if others had any experience to share about their spark plug condition and difficulty to change the plugs with respect to indexing and torquing to the right specs. Seems relatively straight forward, and worth the $75 insurance to change early in my opinion.
Any thoughts and comments are appreciated.
Thanks,
Vinay
SUBJECT: MY-All Model 205, Maintenance Interval
In addition to the information published in the Introduction into Service Manual, note maintenance
interval changes for model 205.
For the extra maintenance operations "Replace air filter insert", "Replace diesel fuel filter" and
"Replace spark plugs", the maintenance interval is reduced from "Every 46,500 miles or 4 years" to
"Every 46,500 miles or 3 years".
Does anyone know the correct spark plug gap for M274 2.0L Turbo engine? Im replacing the spark plugs on my C350E and want to ensure I have the correct gap.
Thanks in advance for any help in this DIY.
Does anyone know the correct spark plug gap for M274 2.0L Turbo engine? Im replacing the spark plugs on my C350E and want to ensure I have the correct gap.
Thanks in advance for any help in this DIY.
The part number i got when i changed mine was A0041597903. These are SILZKFR8E7S, and comes pre-gapped at 0.028".
That's awesome, thanks...the updated parts catalog has a new part number that supersedes the old one. 270-157-07-00...not sure what's different...looks exactly like the old part.
Just wanted to share with the forum.
The OEM spark plug part number is NGK - SILZKFR8H7S, they look identical to E7S probably just a newer revision. All 4 plugs came pre-gapped at .025, so adjusted them to .028.
This part number seems to be the new standard spark plug for all M274 engines. I will post comparison pictures once I've completed the job along with any notes.
Interestingly enough on the CLA forums, the M274 spark plug replacement procedure recommends blowing & vacuuming out your spark plug opening.
Blow and vacuum Once before starting, and vacuum (with tiny hose attachment on shop vac to reach down) before re-installing plugs to ensure no debris falls down into the cylinder.
Thanks to all for the feedback.
I actually called NGK to see what the deal was. The H7S was available as a standard plug on NGK's website, 90654 I believe. The E7S was not. he said the E7S is MB proprietary, hence a dealer only item which they make for MB. The new PN is the H7S. I bought 2 sets of plugs, one for my w213 with 24k on it (following the 3 year rule here) and my wifes x253 (for when it's time). Planning to change mine in the coming weeks.Let me know if you have any issues removing the rear 2 coils.. I always see videos doing the front one without wires in the way, curious on the back ones and any snags you hit.
Hi Folks,
Here's the condition of the 4 plugs, at 23K for the C350e hybrid. These are the E7S variety plugs, which are generally in good condition...note the old plug gap was .025, was aimed towards the injector generally (meaning they were indexed) my replacement OEM H7S I re-gapped to .028, and there was no way to index them without stripping the threads. One ended up slightly facing the injector...the others were not. My problem was the rough idle and the rough switch when the gas engine kicked in from electric to gas+electric. Replacing the plugs fixed both problems, much smoother and the surge when accelerating in sport+ mode is exhilarating. I'll note the MPG on my next long highway run...
Changing the plugs was relatively straight forward. To facilitate removing the rear two plugs, I removed three torx bolts holding down the large wiring harness adjacent to the plugs, towards the rear of the engine. I did not disconnect any of the ignition wires at the top of the engine, and used a long screw driver to help evenly lift the rear most ignition coil.
Other than the potential issue with indexing that I have yet to notice....the plugs look identical... One visual difference is that the washer on the E7S(the old plugs) is washer color was copper...the washer on the H7S matched the rest of the plug...shiny nickel looking color. Neither washer looks like a crush washer, so I don't know if the washer color means anything.
Sorry I did not think to take a picture of the two side by side...but from what I recall the E7S a& H7S length was identical...when you pull your plugs, that would be a "good to know" fact to document here.
BTW, drove to the office today in E-SAV mode, so all gas and a little battery charging and am already seeing an improvement in smoothness when the gas engine cuts-in and overall lower consumption based upon the meter in the dash...
Previously the meter hovered around the 20 MPG mark during light acceleration and occasionally made it to the 40 MPG mark, and now its hovering around the 24-26 mark...and frequently gets to the 48MPG mark while driving...of course while decelerating the engine still shuts off. Still needs a long highway run to gauge final results, as the old plugs capped out at 33 MPG on the highway.
The smoothness is what I was after, and this did the trick...Since it was an easy job to do, I plan to do it again at 46K or 3 yrs.
Your old plug actually looks better than mine...thinking the hybrid drivetrain may strain the plugs more than normal due to frequent (cold) start/stops.
Lemme know if you noticed improvement in running/MPG.
Also, were you able to index the new plugs?
Your old plug actually looks better than mine...thinking the hybrid drivetrain may strain the plugs more than normal due to frequent (cold) start/stops.
Lemme know if you noticed improvement in running/MPG.
Also, were you able to index the new plugs?
I just ran a bottle of fuel system cleaner through it before changing the oil / plugs. Perhaps that helped. I also disabled start / stop.
didn’t bother indexing - the WIS says nothing about it.
Not sure what you mean when you say you didn't index. I am not knowledgeable but this MB article says to me that indexing is critical.
You used OEM plugs and, the way I read the article, if you applied the proper torque, you did index....
Not sure what you mean when you say you didn't index. I am not knowledgeable but this MB article says to me that indexing is critical.
You used OEM plugs and, the way I read the article, if you applied the proper torque, you did index....
i don’t think it’s as critical as they say if there’s zero mention in the MB work instructions about it for this engine. I’m not sure if the spray pattern on these injectors is different than the engines mentioned in the article - and yeah i torqued per the instructions as well (23nm)
i don’t think it’s as critical as they say if there’s zero mention in the MB work instructions about it for this engine. I’m not sure if the spray pattern on these injectors is different than the engines mentioned in the article - and yeah i torqued per the instructions as well (23nm)
I used this from Amazon....worked perfectly...14mm 12 Point Thin Wall Spark Plug Socket 3/8 inch Removal Tool Compatible with BMW, MINI, Nissan, Mercedes
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