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Changed 2015 AMG Spark Plugs today- TIPS

9K views 6 replies 3 participants last post by  Whiterabbitt  
#1 ·
Hi Everyone, just a few quick tips for this procedure. Someone here had posted this MB procedure follow on for mechanics, see attached, as it's helpful.

So very first go search spark plug change for GLA 45 AMG (A45 vids same), very helpful to watch one or two. there is one that is 27 mins. and spot on with what I did.

TIP 1: My car has 31.7k miles, however I let this go past 7 yrs. as these were original plugs. Don't do that. As mentioned in other posts, things were hairy for me when I could not break the first plug free with a 3/8ths wrench. I went to a more comfy 1/2 and carefully applied more torque, taking my time and making sure I stayed square. I did finally break one, and of course all free.

TIP 2: Per the MB procedure, not only do you need a vacuum but it's best to have a blower. For the hose, like in other posts I did not buy the MB kit, but rather got lucky that a used turkey baster I had (minus the rubber bubble) fit perfectly on the end of the flexible vacuum hose and is long enough to reach into the holes. For the blower, I spent $35 at Walmart for an Air Duster (for keyboards and what not). Shaped like a gun, it's rechargeable and blows at 51k RPM full power and was plenty of power, plus had a 6" long tip extension which reached in holes. You MUST do this and do it right, after you have removed the coils/coil wires, before ever trying to take the plugs out, you will have sand and crap at the bottom of the holes. The plugs as you will see are at the front of the block, up top, sitting largely straight down, so it's not weird that sediment over time will get trapped in there.

Tip 3 Onward: Took my time and since I watched vids was an easy project lasting 90 mins. Could easily do quicker. The plugs are NGK (MB OEM if you look close are also made by NGK), SILZKFR8D7S, but on NGK site the new part number will be SILZKFR8G7S, gapped at .028 (this is for 45 AMG's through 2020 I believe). Make sure you have a good 14MM spark plug socket that holds the plugs, mine was magnetic plus has these little steel grippers inside and worked perfectly for $10 vs. MB socket at some crazy cost. Strongly advise spending $10 on ebay and getting the MB spark plug connector grease. Shipping was free and this was a MB wholesaler. Finally, I will do a 4 yr. schedule next time, despite the fact I will have likely only driven 12k. Oh, and there are 3 different sockets you will need for bolts during removal/reinstall: first was a 5/16ths for 3 bolts as shown in vids, second is a male T30 torx to remove a bracket above one of the coils that is in the way, and finally I used a 1/4 12pnt for the coils. I tried various metrics but these were snug, besides, coil bolts only require 9Nm of torque, and by the way, the spark plugs only need 22Nm, which is 16.2 pounds of torque, use a torque wrench to get this right.
 

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Discussion starter · #4 · (Edited)
Yes, so to answer both Q's above, the plugs that came out were just fine, if you look at the vids on other removal procedures, mine were fine since only 31.7k miles. The issue I warn of is 7 yrs (anything over 5yrs probably not a good idea since very hard to remove). I checked the gap, it was wide for .028 but could not put .030 through and otherwise normal wear.

Cost, yes, huge difference, I was quoted $400 local non dealer German repair shop and dealer I guessed would at least be $375 or more. The NGK plugs which are what MB uses and puts their chicken foot on are $16 ea. from Walmart, plus the $35 air duster I mentioned. The grease I have enough for another change. So basically this time cost me $125 for plugs, air duster, grease, and socket. Next time $65 for plugs and 75 mins. of my time.

so the savings, next year when I go in for oil/filter I will talk to dealer about cost for coolant change, or perhaps another tranny fluid change and this savings will pay a good portion of those costs.
 
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Discussion starter · #6 ·
By the way, thanks.

I had an ignition coil fail last week, my great shop took care of me. So since it is clearly a concern in my car, I put in a turbo blanket and swapped out the remaining 3 coils myself, preventatively. Took less than an hour, zero issues, now I'm on fresh coils and ready to go for my next spark plug change. That'll save me $400 when the time comes.

:cool:
How many miles on your car? You are saying the coil nearest the turbo went out, likely due to the heat? When I was doing the plug research I seem to recall coils are not that expensive, maybe $50-60 each? And yes, from my post it is super easy to remove a coil for replacement.