my car currently has 82k miles and has never had its spark plugs replaced. i ordered a set of iridium IK16's off ebay (140 w/2 day shipment) and a set of magnecor KV85 wires (200 w/2 day shipment) last week. i recieved the plugs on saturday and the wires came in today. taking car into shop tomorrow morning to have them installed after i have my injectors cleaned and flow tested.

ive seen other peoples plugs after 50k miles and they looked terrible, so im anxious to see how much my motor has been suffering due to 82k mile plugs and wires... i will retain the plugs and take pics tomorrow to post here

10+ years is a very long time for plugs in an aluminum head. Any head for that matter, but especially aluminum ones. Hopefully they can pull the plugs without any surprises. I'd park it at their shop overnight and let them start work the next day on a cold block.

thats a decent idea but ill be dropping my car off pretty early tomorrow morning, and picking it up before rush hour around 330. there should be enough time for the motor to cool down.

Pardon me, but what exactly is the danger in puting in the new plugs?

This is something I need to do to my car as well.

Thanks,

The danger isn't in installing new plugs. It's in removing the old plugs. The plugs in my car have a spec of 5 years or 100,000 miles - whichever comes first. When removing the plugs after an extended interval (some period significantly longer than the 5 year spec), occasionally the threads in the head are damaged. Basically, the threads partially come out with the plug. The fix for damaged threads is to remove the head, drill out what's left of the old threads, and install new threads with a helicoil kit. That's the reason for using anti-seize on the plug threads. If you're changing plugs every 5 years or so, this shouldn't be a problem. For 10+ year old plugs, the engine should be dead cold as the steel spark plug threads have different rates of expansion/contraction than the aluminum threads in the head.

you don't ALWAYS need to remove the head, just depends on which cylinder it is.

Does it really make a difference remove the head don’t. Why even go there Marcus isn't saying this to wasn’t your time he is trying to help you out! The sad part is he may actually know more then your shop does about these cars. I am not trying to come off as an ***, just giving my 2 cents. If he is recommending that you let the engine get completely cold and not just cold I would listen to the man. But hey its your car do as you please. Hope it goes smoothly.

from what ive read he definitely knows what hes doing. however, my mechanic's shop is run by two senior mb techs who have worked at multiple dealerships and have worked on thousands of mercedes, so i take solice in the fact that they also know exactly what theyre doing...

had the plugs and wires installed. my mechanic had a digital boroscope he just purchased and wanted to use it on my motor. so he took one of my plugs out and slipped the camera into the cylinder to discover a severe amount of accumulated carbon and ****. it was terrible. he uses a cleaning system by BG which has 3 applications, to disengage the fuel pump and run the motor using a pressurized container via the fuel pump pressure test valve located on the front of the fuel rail. he then runs an atomizer with a second solvent which is applied via air intake. the third can goes into the fuel tank to help clean the rest. after the treatment we checked the cylinder again and the black soot now had light brown patches. i went out for a drive and returned to check it out again. i was amazed. 2/3rds of my piston head was shiny metal once again, with small black patches here and there. he assured me now that the deposits are softened they will burn off in the next 500 miles. i wish i had my laptop with me so i could have captured the video data from the first couple inspections (the boroscope has a video out port). ill be taking the car back on monday to check it out again to see if the treatment followed through, i will post pics and perhaps a video...

had denso iridium IK16 plugs and magnecor kv85 wires installed after the treatment... the car runs like an animal, so much smoother and much much more powerful.

takes 2 hours or less to do your own plugs.Get 16 NGK 7090 plugs for about $2.79 each.
Accepted Linear Expansion Values of Common Materials
Material
Steel 1.24
Copper 1.76
Aluminum 2.34
Coefficients of Thermal Expansion at 20C
volume of aluminum expands at a linear progression of steel.A spark plug expands less by a rate approximately of 2:1 of the head.
A slightly warm plug is easier to remove then a cold plug from a cold engine.
The plugs are plated with a trivalent Metal anti-seize anti corrosion. No anti -seize need be applied to modern spark plugs.If you torque your plugs the tq. will be wrong.If you get the tiniest bit on the electrode you will fry the plug.
Read your shop manual,no anti-seize.
Read the spark plug manufactures guide lines,no anti-seize.
We have removed plugs from M112 and M113 engines at in some cases had over 120,000 miles on the oem plugs no issues with the proper socket and engine just warm to the touch.7 year old plug and the only wear was a few thousandths on the gap.
Get yourself the 17mm offset Spark plug boot removal tool,makes that job a piece of cake.Leave your wires on the coils.Your wires stock will if not abused transmit all of the coil voltage the M113 or M112 engine ever needs,and do so for the life of the car.Unless you yank them off of the plug
Last month I hosted a spark plug tutorial for some members on the w210 section.A w210 sedan with 125,000 miles on the oem plugs and a C320 fully modded. Both cars with rookie Mb plug skills and they were both done in under two hours with the proper tools.
A V8 can be done for $50 and a basic set of tools,a torx bit,and the 17mm boot tool.All by yourself,A can of cold beer or two for a grand total of $100 if you did not have a tool kit and the 17mm boot tool to start with.
Maybe some people enjoy having the shop do it and paying them $500 0r $600 to do what a diy owner can do for $50-$100.I prefer to spend the $550 saved on other toys.
ohlord
Spark plug diy on benzworld.org w210 section
Tool up
"GOT CODES?"

under normal circumstances i would agree. but i only paid my mechanic 100 bucks to do the job, and had i done it myself i would be upset with the fact that my time is way more valuable than 50 dollars per hour. he had no issues taking my plugs out, but the 82k mile old plugs were in terrible shape, the electrode was completely missing, and the base started to wear away too, the side facing the ground was starting to slant quite noticeably. whereas this doesnt cause problems, it lessens your peak performance, which is what ive been after.

You get the same exact results from seafoam without any of the hard work. Put a can in the gas tank and put a can into the engine via vacuum lines, will clean up EVERYTHING. The stuff is unreal. Took my C36 engine apart and literally the pistons were spotless as were the heads after the injectors, zero carbon deposits.

Seafoam is $7 a can, get two and you have pretty much a new motor.

Regarding wires & plugs, They never really add HP, they just smoothen up the way the engine revs. For forced induction its more necessary than NA but either way its not about getting more HP, just getting higher quality spark and smoother acceleration as a result.

you get power gains in that a 82k mile old plug does not facilitate the full potential of the motor. so replacing the plugs in my case helped with power and smoothness. my car is noticeably faster when compared to friend's cars which i raced before and after the change, i was able to put in more car lengths as compared to before. i tried seafoam already but only did one can so im not sure how much it helped, this was about 2 months ago

and electrode burned down?Something is wrong with that engine,or the po ran it on low test and lugged it around town.Have the o2 sensors been tested?
Someone drive it around with a cel on and ignore it.Something is up in that engines past and I would take it easy on it till you have it diagnosed,for a baseline.
ohlord
"GOT CODES?"

everything is fine with the motor, no codes, and the car is making great power. the plugs were missing the tip of the electrode, not the entire electrode. but thats what happens with the electrode it gets eaten away as the plug ages, you cant do anything about it, its the same principle that arc welders run on.

had o2 sensors replaced already. when i got the car it was having lots of issues, replaced o2's, MAF sensor, and the oil was in terrible shape. the car really made a great comeback since then which ive been very happy about.

Spark is much bigger issue with forced induction b/c it can easily blow out causing misfires & etc. I'm glad your car is running better.