I found the problem to the rough idle, bad MPG, and everything else associated with it! It's my SPARK PLUGS!!!!! Today I took it over to a friend's house... took one out and it was rusting and BLACK. Really bad... Anyone recommend where I can buy plugs from? And what kind? Also is there anything the plugs could have damaged that I should look out for?

Thanks Guys... been a great help!

 

NGK or BOSCH Platinum.................

BTW check the spark plug lines maybe they're getting old and are in need of replacement

 

Is that all? I thought there was a reason they got bad (im hearing compression or valves or something like that)... well the car's driven about 60k miles and the plugs on it were OEM... straight from the factory, so I'm guessing its all normal.. well I hope.

 

dude just go to a certified mechanic and get teh car tested, sounds like something is fishy.

 

Fishy as in there is more bad stuff on my car?

 

not necessarily and I hope u actually inspected the car before you purchased it

 

Haha, nah I didn't... I was told they are "bulletproof" well I don't care... It's my baby and I'll take care of it. Just pinpointing problems is hard.

 

they are "bulletproof" alrite just don't take that overboard

 

HAHA... yeah I won't, but thanks for helping guys! Oh... I am going to order the OEM NGK plugs it came with... 3 dollars a piece.. sounds good?

 

yeah pretty good price but like I said have the spark plug lines checked as well. Don't want those plugs burning out too quick

 

Oh for sure... especially that. I'm just worried about compression or somethin like that... I'm wondering what caused my spark plugs to go bad.. or could it be age?

 

u see, what you're doing is just blindly throwing new parts at your car and not knowing what the root cause of the problem is. that won't get you anywhere

and fyi, mercedes are NOT 'bulletproof'. in fact, i always swear by this old saying, "the most expensive used car money can buy is a cheap mercedes". you'll find out

 

Well let’s see, why are your plugs bad? Maybe low grade fuel like REG 89, car cooling system was overheated, too much fuel additive, too many miles on them 60,000 miles is about time to change them out and so on. Replace them all about 4 hours take your time and test drive again if still similar problem replace your MAF and everything should be good. Did they change your oil before purchase? Use 8 quarts Mobil 1 0w40 or Royal Purple 5w40 or 10w40. In fact you should drain your trans oil and replace filter very easy to do (Use factory trans oil about 4 qt unless you drop your trans cooler lines to give you 6 qt. total) and replace the rear-end oil with Royal Purple or Redline gear lube (about 1.5 Quarts). There are DIY on this forum do a search for all these repairs. This will help you understand your car and save you money on taking it in to a shop. If you don’t want to do the work yourself find a good shop from friends or someone on this forum and you will pay around $1500. give or take for all the above work. Oh and purchase a WIS DVD Manual.

 

Oh yea, the black stuff on your plugs is carbon build up, MAF Bad use only Bosch MB!! That’s why you have to run the fuel additive to clean your valves and plugs but still replace the plugs they need it.

 

Thanks for all that Dawson!!! Appreciate it, so your saying my MAF is bad too?

 

These cars are bulletproof; assuming you properly maintain them. You can replace the spark plugs, replace your fuel filter, and replace all your fluids. In fact, I did when I first purchased my E55. I spent the $$$ for peace of mind. The funny thing is that in the end the culprit was the MAF sensor. Go figure. My money is on the MAF sensor. Enough said.

 

Let's hope not haha.. my plugs do look bad tho. Either way I need to get them replaced. I wonder if I need to fix anything associated with the plugs? Anything at all? I'm hearing stuff about coil packs.. hmm?

PS. What kind of plugs should I buy... a bit more specific, including gap-size. Thanks. When I saw the plug today... it said NGK on it with a Mercedes logo on the other side, looked OEM... I'm not sure but I'll put NGK in it again if needed.

 

come to think of it sometimes I wish we had Royal Purple oil in here. Only good oil is Mobil1

 

With the car properly maintained, the plugs should go 100k miles but these sound to have too much build up. I just bought plugs from the stealership (I can buy wholesale with tax) and they are Bosch Platinums as recommended.

I hear that the plug wires to get are Magnecore 8mm, is this correct?

 

I went into a local shop, the owner owns a Benz too... he's charging me 150 bucks for labor only... how does that sound? Any advice if that's a good price?

 

I don't know if that's a good price for a mechanic but it still sounds a lot to me because I'm planning on changing them myself. My buddy is a mechanic in Pasadena so I'll give him a call tomorrow and ask him...

 

If you can turn a wrench you can replace the spark plugs on your own. Save the $150. Also just because they went bad doesn't mean that anythign else has to be wrong. There is a lot going on inside the cylinders and parts wear out. Especially spark plugs. I've replaced the plugs on all the cars I've owned more than once and there was never anything else wrong other than the spark plugs. Don't freak out about it until after you've replaced them and see how it runs. Saying they should last for 100k miles is way too optimistic. There is nothing abnormal about the spark plugs getting fouled up in 60k miles of driving. Granted that doesn't mean something else isn't wrong for sure, MAF's do have a habit of dying it seems, but its not a guarantee.

 

That would be great Jimmy... thanks a bunch! I hope it works out I appreciate it alot.

 

I just got off the phone with my buddy. I'm going to see him at the shop on Saturday morning so I will have more info on prices.

 

Repair rates are from $65. to $150. per hour of labor and depends on the shop and city. Is this to change your spark plugs? 4 hour job that seems very fair if you don't want to get dirty. I have not replaced my plugs on my E55 yet but hear it takes 4-6 hours depending on who’s doing the work. All are pretty easy but the driver side last 2 plugs. Your plug wires may need to be replaced after install because sometimes they get broken during the install due to age and handling.