What else other then then the plugs does that cost include? Did you change your plug wires too? Need to do mine as well. Thanks :)

just the plugs. People have difference of opinion on wires, but I am not changing mine since they should last a lot longer than the plugs themselves (unless handled incorrectly and not using proper tools) and the manual does not call for them to be changed either.

Plug wires
 

What we did was unplug the wires from the coil pack and then replug them. This wipes any corrosion buildup on the connection.

No doubt many stealers replace "defective"plug wires rather than performing this venerable procedure.

We used a dab of anti seize on the plug threads and a dab of dielectric grease on the boot wire to plug connection.

Finally, after all this, if you get a misfire try switching spark packs from one cylinder to another. Be careful because the wires and packs have an interchangeability order, they are not all the same. I took a before picture of both banks as well as looking at the diagram on
www.mymercedesparts.com
For a further reference to the M113K engine.
Just some tips. Comment: The spark packs on the m113 and m113k v8 are epoxy sealed and should be quite rugged vs the infamous v12 packs in the turbo environment.:smash:
:zoom:

Great. Excellent suggestions. Thanks.

FYI - The manual (page 481) says the proper gap is 0.031" (0.8mm) for the e55.

That's for stock. If your running a lot of mods and more boost you should tighten the gap slightly. I was running .027.

Sorry if this is a newb question... but what is the technical advantage of running the colder plugs?

My car is stock w exception of EC tune.

Thanks

Less detonation prone with colder plugs at higher boost levels. I'm sure your fine with stock plugs on a tune only. :y

cool...thanks... I may add SC pulley in the spring (Would like to break into 11's :) ... that will probably be all i do performance wise.

Ok another dumb question... just to confirm are there a total of 8 to buy?

16 total

you need 16 ! 2 per cylinder

Here is what mine looks like... I assume a good candidate for replacement.

http://i193.photobucket.com/albums/z...EF0D4CEF0A.jpg

^^ Are you logging your AFRs ? My guess is you are running rich....

it doesn't look horrible -pretty normal for the mileage, but yes, replace them :)

here's a good pictorial of what happens to plugs
http://www.ngksparkplugs.com/tech_su...qs/faqread.asp

Im not logging them. I have EC tune... does that make it run more rich? Any recommendations on how to log AFRs?

You should get a wideband installed (Zeitronix and Innovate are the leaders) or find someone with a portable wideband and drive around and log....I am sure you'll see the box tune is very conservative (rich). Although the plugs don't look bad, they do look like you are running a tad rich (I have seen much worse).

2006 cls55 manual says .031" or 0.8mm

2006 cls500 manual says .039"

hope this helps clarify

Regarding gaps, my 2005 E55 manual says 0.031" or 0.8 mm.

Based on my small sample of NGKs, I recommend checking the gaps on new plugs rather than assuming they are all accurately set at a predetermined gap. I just bought and gapped 18 of the NGK LFR6AIX-11 plugs. Yes, it's a small sample, but the gaps were definitely not consistent across the batch. Three of the 18 were at the gap I was setting (I used 0.032), and the rest were closer to 0.040.

My car is currently stock. Is there a difference in the smooth idle with a one stage colder plug? If so I'll go stock plugs until I modify.

Stay on stock plugs until you mod going one step colder will be more trouble than worth imo

How so??? Going 1 step colder really shouldnt make much of a difference in all reality. Should idle the same cruise the same an run hard just it keeps detonation more at bay. They dont stay as clean as the stock but its cus their not burning off the deposits as fast as the hotter plug. But i change my plugs every 4 monthes anyway just because its nice to have a fresh set in there and in reality their not that expensive ... its like doing an oil change and takes bout an hr.

But maybe some of our cars dont like the colder plugs mine loves em and it drives, idles, and cruises exactly like it did with the stockers heck even my mileage is same.

My daily commute is like 1.5 miles (5min in traffick) from home to work and back. I don't really get all the way up to op temp and I think this contributes to my plugs fouling a little. The idle for me really smooths up when I've been beating on it, until then its a bit rough. It could be my injectors though? I am putting a new set of 1 step colders in. I have one bank done last night the other bank today and I'll let you guys know if its smoother from the change. Everything else, MAP, IAT, o2, coil packs and wires are all replaced within the last couple of years. My thought is if you are on stock you will have problems with plugs fouling up and slightly rougher idle. NGK recommend going to one sop colder when increasing power by 75-150 hp if I remember correctly.

You must be fast to get all 16 plugs done in an hour! I spent a good hour getting one side done, but I didn't copper grease the plugs last time so I have to turn it like 7 times before it starts loosening up and turning easily :P. Also I don't have a good extension length and have to work around with too short and too long :D.

I find my idle is more temperamental with the colder plugs I think it is because my daily commute to work is like 2.5km and car barely reaches OP temp. I do my best to smash the pedal on longer drives but I think the plugs foul up quicker, figure since hes stock no point changing to get potential headaches for no real benefit ngk said every 75-150hp go one step colder if I remember.


Maybe my idle is the injectors we will see I have new plugs going in now did one bank last night do the other bank tonight.

You must be fast to get them done in an hour, I have to struggle against the plug for like 7 full rotations before it starts easing up on me. Probably should put some copper Q1qQQwzQqqqqqwww²grea222w3w33a2qq in grease on. I also am a bit short on appropriate extensions and either have too short or long so am working around that lol