400HP55

I've read lots of articles on the spark plug ordeal. Just wanted to know one last time before I buy them:

MB OEM Plugs for 215.00

Or Bosh/NGK Plugs for 125.00

Maybe I'm not understand what the big difference is??

I hear NGK is good to. What is a Sprak Plug Supressor? They told me that there are supressors on some of thm??

What to do?!?!?!

Thanks guys!!!

MarcusF

Bosch was and is the OE manufacturer for Mercedes-Benz plugs. The original plugs are no longer produced and have been replaced with Bosch part number FR8DPP33. I paid $125 for a set of plugs at a dealer several years back and the plugs that come in the Mercedes boxes are Bosch FR8DPP33. Currently you can buy FR8DPP33 plugs for $4.50 each / about $75 per set from Autohaus AZ.

Suppressor plugs are used to eliminate/suppress radio frequency interference and electromagnetic interference. (so are suppressor wires) If you’re unfamiliar with what I mean, there was a time when it was common for a guy on a motorcycle to pull up next to you at a light and cause your radio to get a lot of static. That static was radio frequency interference caused by the motorcycle’s lack of suppressor wires and suppressor plugs. If you have non-suppressor wires and non-suppressor plugs in a car, the radio will sound horrific AND as an extra bonus, the electromagnetic interference will cause the ECU to behave less than admirably. I’ve never tried it, but I’m fairly certain it would drive a cell phone, especially a smart phone, absolutely off the deep end.

At any rate, if you buy the Bosch plugs you'll be fine for another 5 years or 100,000 miles (whichever comes first). I recommend using a spark plug wire puller. They're about $20 at sears, which is about a tenth of what a new set of wires cost when they're on sale. FULL LIST for a set of wires at a dealer has been known to bring a tear to the purchaser's eye.

400HP55

Outstanding knowledge!

One more question:

I keep getting told that iridium is OEM? But OEM is platinum? What's the difference and which is better?

Thanks!!

MarcusF

The original equipment sparkplug manufacturer for Mercedes-Benz is Bosch. The original plugs that came in all M113’s were platinum. The K motors use a different plug than the NA’s - but all of them are Bosch platinum plugs. The current M273’s use Bosch platinum plugs as well. I have no idea what’s used in the M156 or the V12’s, but I’d be surprised if Bosch didn’t get the contract for those too because all the other electronics are Bosch. The only Bosch iridium plug that I know of is a combination platinum-iridium /4 ground electrode plug. They may make a plain iridium plug, but I don’t anything about it. I can say this - I wouldn’t use a 4-ground electrode plug if they were free. If you don’t know why, Google "indexing sparkplugs" and then look at a 4-ground plug.

Both iridium and platinum are metals that are used for the sparkplug electrode. Iridium is both harder and stronger (not as brittle), has a higher melting point, and there are probably other marketing reasons for using it. Which is better? If someone is running a boosted engine, probably the iridium plug (I don’t know anything about iridium and heat retention, you'll have to do your own research). For a non-boosted car, I don’t know if it matters. For me, I can’t see how it would matter. I saw the plugs that came out of my car. They had 90K+ on them and were just under 5 years old. The electrodes weren’t worn out, so iridium being harder isn’t a selling point – they’re still getting changed at 5 years/100K. Iridium has a higher melting point, but if I’m melting platinum electrodes, I have much bigger problems than which plug to use.

Honestly, use whichever one you feel good about. I use Bosch because they have a track record with my particular motor. NGKs, Champion, Denso, may work just as well.

400HP55

Where did you find the information that FR8DPP33 plugs is what the dealership uses?

Thanks! Great info!!!

400HP55

Has anybody used these on there AMG???

MarcusF

I walked into my local Mercedes-Benz dealership and bought 16 plugs. 1 box of 10, and 6 individual plugs. The dealer part number is 004159190326 and each plug has Bosch FR8DPP33 printed on it.

Call your local dealer, ask them if they have a set of spark plugs in stock for your car, and what the part number is.

clkguy

the 26 designation after the part number tells you that this is a revised version of whatever was originally used. not superceeded like from one brand to another that would justify a complete part number change. just the end prefix tells you its a improved version. maybe a change from platinum to iridium electrode etc.

400HP55

Yes mine had the same part number. But if they had FR8DPP33 stamped on them then that means they are Platinum and the number at the end means just a newer model, but still platinum?

ohlord

was a f8 resistor type plug since upgraded to bosch 7422 fr8dpp33
about 4 bucks each at your local autozone etc.
Get the 17mm special boot tool, don't use anti seize,toss them in and you're good to go for another 5 years.

clkguy

i take it for granted that you would anti sieze on the plugs. alloy heads and an extended lifetime, so they are meant to be in for 100k. i took mine out when i installed magnecoor wires at low miles so i would not have the problems down the road. even though i would never ask a plug to last that long.

ohlord

usually happens first.

don't use anti seize is what I wrote.

unlukky

Damn !!! Marcus' answers are spectacular.

DRBC43AMG

Always

clkguy

no anti sieze is based on what. dealer, private tuner, best buddy's advice?

400HP55

Just pulled the trigger on some. They will be here Tuesday! Will update with some pics. FR8DPP33 X 16 from Autohaus Online.

ohlord

the 17 mm special boot tool?

No anti-seize is based on Knowledge putting in plugs, It can short a plug,it messes up torque settings, and the maker of the plugs states clearly use no anti-seize. They are treated with special trivalent metal eliminates the need for anti-seize.

400HP55

Ha! Took 5 hours. But I took breaks. Man that was sort of a pain! Car feels a LOT different. Way better. The wires were in really good condition. All the plugs I took out were all exactly the same color. Engine is in tip top shape! I took out NGK R plugs. Thanks all for the help. Perfect thread if anyone wants details for this job, or which plug to use. I also cleaned the engine while I was in there. Here's the DIY link to:

https://mbworld.org/forums/w210-amg/...wires-pix.html

You guys helped a ton! Thanks again!

400HP55

Oh ya, forgot to mention...

I did with $95.00 =D

400HP55

I just talked to my mech at the mb dealership and he said that my spark plugs (The ones listed above) are the wrong ones. He said they are the resistor type plugs and we need NON resistor type plugs. Anyone know anything about this??

MarcusF

The OE plug was nonresistor plug. It's been out of production for years. Mercedes-Benz replaced/superseded the OE plug with a resistor plug. Go to your dealer's parts counter and ask for a plug for a CLK430. They'll bring you a 004159190326. Then look at the plug, It will have a Bosch part number on the plug itself. The "R" in the part number is for resistor. Or better yet, ask your tech to tell you the correct Mercedes-Benz part number.

400HP55

Exactly, but the mech (25 year master mech) insisted I had the wrong kind... He said I needed non resistor...

MarcusF

That means someone is wrong - either the mechanic or Mercedes-Benz.

400HP55

Both the dealerships and MB is wrong cause MB hires some mechs who don't know JACK

400HP55

MarcusF,

Could you please explain something to be I'm a bit confused.

If our wires are resistor and the above spark plug is resistor, how does that effect performance?

Would I be able to buy non resistor wires and run the opposite set up (opposite from OEM). And if I did this would I be able to tell the difference?

Thanks man!