McKyle

I took my 2005 E55 in for a dealer service because it is a CPO car, so I figured I'd pay the extra dough to ensure compliance with MB service requirements. They said I should replace the plugs on a time basis. I have about 39,000 miles on the car, but it's been 5 years. They said to replace them or the threads will seize in the heads.

Well, the plugs cost $417 to replace, but the problem is, it doesn't look like there are enough disturbances to the dust on the inner fenders (I'm in New Mexico), hoses, etc., that I can be sure someone was in there and actually replaced the damn plugs - they look somewhat untouched. So the question is, after 25 miles to get home, what should the plugs look like if I pull one on each bank to verify they were changed - brand new, silver?

Second question, what is the best way to remove the wires without damaging them, so I can pull the plug with a 5/8 deep?

Last question, would there be certain plugs they might avoid in order to flat-rate the job? He called me after 3.5 hours saying the car was done, but charged me for 6.5 hours. I understand the flat-rate scheme having been in the auto business in the past, but not knowing these cars real well, I'm not sure if the job was flat-rated by an expert who knows what they're doing, or cheat-rated by an expert of a different type.

Thanks for any suggestions and help.

McKyle

Forrest Gump 9

Even after 25 miles the sparkplugs would still look new. You'll definitely can tell the differences between 25 miles plugs and 39K miles/5 years old plugs.

ohlord

the engine cover coming off and the coils being moved to give access to the plugs you won't see a lot of evidence they have been replaced.
With the special boot tool it is an easy diy job takes about 2 hours you actually got off lightly I have seen people charged 8 bills for a 320 plug change.You need not use the dealer to retain your CPO you are allowed to do services or have them done by an indie shop and written down in your service book.It's the law

izzyz28

Pull off a couple of wires and look for a color difference between the covered porcelain and the uncovered porcelain on the plug. Also, if the plug wires are stuck on, the plugs haven't been changed. If someone did the job, there will be evidence! Look at the dust and dirt that's collected in the heads of the coil bolts, has it been discturbed?

McKyle

Thanks to all - I will check it today. I'm in hopes they changed them, but at first glance it looks like I was ripped off. I'll get a few out of there today and have a look.

Thank you again for the advice.

shardul

iTrader: (1)

us a 17mm open end wrench to pop to ignition wires off, then use a swivel sprak plug socket with an extension to remove the plug. you can gain access to the first plug on each bank with out removing air box or coil packs

McKyle

Thank you - what should the plugs be torqued to on installation?

shardul

iTrader: (1)

i cant remember just make sure they are sung and you will be fine. it is almost impossible to fit a tq wrench on all the plugs.

McKyle

They had done the work - the plugs I pulled were new Bosch plugs. Thanks again for the advice!

Viet_Amg408

So they say if you don't replace spark plug on regular basic. or the threads will seize in the heads? thats full of bs.. only time that would happen if your headgasket is leaking coolant into the cylinder.. guess they scared you into doing it..

slownrusty

I just replaced all the plugs on my '06 E55 at home, my car is also CPO...the dealer does not have to do them to maintain the integrity of your CPO warranty (if they told you that, they are feeding you a line of B.S), you just have to ensure you go back with the same spec plug.

The dealer is correct, after 5 years you really need to change the plugs regardless of how often the car is run and no. of miles are on it. Reading plugs is a science and not many of us can do this, I can show you a plug that has 5,000 miles and another plug that has 50,000 miles and they look the same.

The quote from your dealer to change the plugs is about right, I have to ***** at you for a bit, these are $100,000 cars and the dealer will obviously charge a premium rate to work on your car, as they have factory trained techs.

I find alot of people on the forums are penny pinching when it comes to maintaining these cars and cower when they see the prices the dealership charges, but that is the price of ownership. You need to budget and budget well when it comes to ownership of these cars (I say $5K per year). Lots of folks have been able to afford buying these cars in the $25-$30K range, and then complain at the high cost of ownership when something goes wrong or parts need to be purchased...maybe it is not the car for them. It is great to say you own a 500hp AMG, but ownership does not come inexpensively...rant over.

Back on topic...my car has a few more miles that yours and after I had the car dyno'd at Kleeman, they did say that I would have broken a slightly higher number with a fresh set of plugs as my car was still running the original plugs from the factory and had never been changed, which is why I went home right after and changed them all.

I paid about $11 per plug, and a few hours of my time, so I did the entire job for about $180. No fancy hand tools are required, but a good experience and an opportunity to work on your car and get to know it better.

phatmitzu

What kind of plugs did you get?

slownrusty

Factory NGKs I ordered them from Advance Auto Parts.

rspizzi

Hi all, Does anyone know if Bosch Iridium plugs,part #9652, will fit a 03 E55? The reach on this plug is 3/4". I've read that the reach on the original plugs should be a faction over an inch for the E55. Can someone help?

jpohl402

Talk to me about plugs...

Bosch, NGK, colder ones, etc....
Best choice for our application, with reasons to document.

About to do this project. Thanks a ton !!

rspizzi

Thanks for the quick reply. After much research on the internet I decided to go with the Bosch fr6mpp332. The specs are perfect for the car. Same reach as the originals. Any feedback would be appreciated.

grane

Use oem grade Bosch Platinums or Platinum Plus for best results. Avoid iridiums or plus 2 or 4plugs that tend to run hot, etc. I think the pn in your post above is correct.

nGKR plugs are a good second choice.

Check breather hoses, valve cover gaskets and replace also.

Forrest Gump 9

Are you sure you've just recomended platinum plugs for the 55k engine? If so, do you where to find a replacement engine?

Stick to the stock NGK iridium plugs or run a step colder. If you're cheap, go with copper plugs. But please DO NOT RUN PLATINUM PLUGS IN THE 55K ENGINE!! As a matter of fact, don't run platinum plugs in any force induction engine.

GT-ER

Why? I've used platinum before on forced induction cars with no issues. I curious as to why you think they are bad.

Heck, I thought oem was platinum.

grane

I just looked in the owners manual and the recommended plugs for the Cl 55 are NGK ILFR 6 A!
(the only Bosch are for the M113 only!)

The NGK site recommends pn IFR5 D10 or stock number 4696. I take this is perhaps an updated, cooler plug? If so they are going in pronto!

I stand corrected. Thank you Forest Gump 9! I guess my tech and the MB parts guy were wrong!

grane

Thank you! But the NGK number has been updated from the OM. Can you explain?

AgSilver

For this very reason I believe over time most E55's will end up in the "graveyards of the rusted automobiles" just as most of the W109 6.3's did. This is because most subsequent owners will not have anticipated the costs of maintenance and repair. The E55's that survive in pristine condition will always be desirable, as are the pristine W109 6.3's.

jpohl402

so what is the real story - platinum or not....???

rspizzi

As jophl402 asked, what is the story about platium plugs not belonging in a E55 (03). Mine has 48000k on it and I just ordered bosch platium plugs. Should I install them or not?

jpohl402

so, any feedback on the type of plug that works best or that most here use....??