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Technically, 45,600 miles, I'm always late for things, lol.
I was SOOO glad and relieved that my #1 plug looks the same as the rest. Historically, #1 is the evil cylinder on some M274's :p
I replaced the stock plugs with NGK 90654's. I only wish I changed them earlier, as I can definitely feel the difference. The throttle response is much better, low-end has a little more grunt and pulls harder than before above 3,000 RPM.
So, they definitely needed to be replaced!
Changing the plugs was almost as easy as with a small-block V8... easy project for do-it-yourselfers for $80.
Were they hard to change out? I’m at 26k on my stock ones and they didn’t mention anything about it when I had my service b done two weeks ago
I had my 50,000 mile service performed by MB of Laguna Hills at 33,000 miles because it was due per schedule, the 5 year time frame had elapsed. That service interval includes spark plug replacement. So when you are due for the 50,000 service per time elapsing or milage accruing your plugs will be replaced, in case you want to wait.
Were they hard to change out? I’m at 26k on my stock ones and they didn’t mention anything about it when I had my service b done two weeks ago
Not hard at all, in fact, I'd say it was simple. However easy/simple are subjective terms. If you have basic mechanical skills and tools, it is easy. However, if you have very little mechanical skills, a hammer, and a screwdriver, it's going to be extremely difficult, lol.
In a nutshell, for each cylinder; remove two small bolts on the top of the ignition coil. Pull the coil/boot up off the spark plug and pivot away. Remove the spark plug. Replace in reverse order. Enjoy saving $500+ dollars compared to an MB dealer.
I must say that mechanical knowledge and skill is a valuable commodity that has monetary value. So, even though MB absolutely gouges customers for the cost of replacing plugs, if you try to do it yourself without mechanical knowledge and skill and cross-thread a plug into your aluminum engine, it could cost you thousands. Something to keep in mind.
Some tips:
You can remove the plugs with a standard deep 14mm socket, however, without using a spark plug socket that has the rubber insert to hang onto the ceramic plug stem to pull the loose plug out with the socket, you will need either a magnetic pickup tool or long pronged needle-nosed pliers to get the loose plug out of the spark plug recess (not wide enough to get fingers in there).
The spark plugs come pre-gapped at 0.28 - but check, verify and adjust as needed. Out of the box, I had 3 at 0.28 and one at 0.26.
You'll need a torque wrench that has a range that can be configured for 23nm of torque for the plugs. (proper torque here has added significance for electrode indexing)
Apply a small amount of dielectric grease on the spark plug ceramic stems and inside the spark plug boots. You'll be glad you did when it comes time to change the plugs again..
When placing fasteners/items into aluminum threaded holes, finger torque only and wiggle the item as you thread it in with your fingers. Any tool that adds more torque than your fingers (ratchet, t-handle, etc.) should be reserved for tightening/torqueing only. I've learned this the hard way multiple times in my life. (this actually applies to everything, not just aluminum)
Don't tighten the crap out of everything. I know it seems like the right way, but it is not. Most fasteners on MB's have published torque values for a reason.
Totally agree Keith66, all my service has been covered, my CPO purchase came with 2 year / 2 service included maintenance. MB, like all dealerships, is way overpriced so I wouldn't go to MB for anything other than recalls if not covered.
Back in the day I did all my own repair and maintenance, even swapping out a blown engine. Now I've lost the desire and vehicles are way more complicated than they used to be. I find a good independent shop that specializes in MB at 60% of the cost when I'm not covered by warranty/service contract.
Great step by step instructions on plug swap out 👍
Totally agree Keith66, all my service has been covered, my CPO purchase came with 2 year / 2 service included maintenance. MB, like all dealerships, is way overpriced so I wouldn't go to MB for anything other than recalls if not covered.
Back in the day I did all my own repair and maintenance, even swapping out a blown engine. Now I've lost the desire and vehicles are way more complicated than they used to be. I find a good independent shop that specializes in MB at 60% of the cost when I'm not covered by warranty/service contract.
Great step by step instructions on plug swap out 👍
Very wise indeed... indy shops are the way to go unless you have factory warranty/CPO coverage.
Shortly after I bought my used MB, I brought it to the dealer for the scheduled service which was purely an oil change and check all the things... for ~$700. I think the oil they use is from dinosaurs that have been extinct longer than the rest, lol. I refuse to be screwed twice and haven't been back since, except for a couple of minor issues covered by the factory warranty.
I hear ya and understand not wanting to do things yourself. I think what keeps me engaged and excited is modding the car, which is something I've enjoyed doing to most of my cars/trucks/bikes since I was a teenager (many moons ago now, lol).
Dang, I’m only covered by the factory warranty…I’m afraid to even ask my service advisor at MB Valencia lol
Yeah, prepare to have your wallet emptied at MB.
If you don't want to do it yourself, I would suggest taking it to an independent shop educated in Mercedes vehicles. They are everywhere.
Service is not required to be performed at a MB dealer. As long as you save the receipts and stay on your service intervals, it won't jeopardize your factory warranty.
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