Do I need to replace spark plugs? W210 - PeachParts Mercedes-Benz Forum

Cobra1 · #1 05-08-2009, 03:23 PM

Bought E320 new in 2000. Now only 62K miles on it - wife's. I'm getting ready to change oil, filter, etc. myself. (All maintenance done my MB dealers in past.) In researching, I note that owners manual says to change sparks at 100,000 or 5 years. Looked back thru all my MB service invoices, no spark plug change ever. It's way under mileage but now over 9 years old. Should I change them? It runs great, always has.

deanyel · #2 05-08-2009, 04:04 PM

Yes, the longer you wait the more likely they'll be stuck.

rocky raccoon · #3 05-08-2009, 04:13 PM

It is my opinion and practice to remove spark plugs, inspect them, clean and re-gap once a year regardless of what MB says. You can be certain they will not "freeze" in place that way. I cannot imagine leaving them in place for ten years. Asking for trouble, I think.

Against some advice, I also clean the threads and give them a spot of anti-sieze when reinstalling. Has served me well for many years of automotive and motorcycle maintenance.

pawoSD · #4 05-08-2009, 04:52 PM

I'd pull and at least check them, but with the cheap cost of them I'd just go ahead and replace.

jcyuhn · #5 05-08-2009, 05:10 PM

They aren't really all that cheap - ~$10/each. And there are 12 of them.

pawoSD · #6 05-08-2009, 05:19 PM

Quote:

Originally Posted by jcyuhn

They aren't really all that cheap - ~$10/each. And there are 12 of them.

Whoa, never mind then.

I like my M103 even more now! 6 spark plugs for about $2.30 apiece!

porkface · #7 05-08-2009, 05:28 PM

replace them. if you go more than 60, 70k, then the rest of the ignition system gets stressed. you'll end up replacing wires and coils. way more money then the 120 usd for the plugs. good luck, chuck.

Southern · #8 05-09-2009, 08:45 AM

The 100K miles or 5 years should have stated "which ever comes first". The factory does not put any anti-seize on the plugs or dielectric grease on the boots. You will find not only the plugs difficult to get out but the plug boots will be a pain to remove as well. Plan on spending several hours to replace your plugs.

My 98 E320 is on it's third set of plugs at 163K miles. I changed them out every 80K. The factory plugs were the most difficult to remove, since then I treated the plugs and boots and removal has been much easier.

Johnhef · #9 05-09-2009, 09:44 AM

fwiw, I've done probably a hundred or so spark plug changes on 112/113 engine and have yet to encounter a single stuck plug. Including many well past the recommended service interval.

kchemers · #10 05-09-2009, 09:46 AM

********** has oe plugs for less than $5 a piece

kchemers · #11 05-09-2009, 09:47 AM

lol

david s poole · #12 05-09-2009, 11:17 AM

just for your info the plug wires will prob go bad before the plugs so if you are going to take plugs out[not the world's easiest job]replace the wires at the same time.

HarryM · #13 05-10-2009, 05:39 AM

I am wondering if 100,000 miles is too soon to replace plugs in these engines. On my daughter's 2001 CLK320 I replaced them at 99,000 miles about a month ago. The plugs looked battered and pitted, but replacement made zero difference in fuel economy and zero difference in performance or driveability. They could have been left there for another 100,000 miles.

I agree with removing and reinstalling them with anti-seize about every 50,000 miles.

FWIW it took me six hours to replace them. One of the plugs took 45 minutes of loosening and tightening and lots of WD40 to come out.

Harry

strelnik · #14 05-10-2009, 10:42 AM

Quote:

Originally Posted by rocky raccoon

It is my opinion and practice to remove spark plugs, inspect them, clean and re-gap once a year regardless of what MB says. You can be certain they will not "freeze" in place that way. I cannot imagine leaving them in place for ten years. Asking for trouble, I think.

Against some advice, I also clean the threads and give them a spot of anti-sieze when reinstalling. Has served me well for many years of automotive and motorcycle maintenance.

X2, good idea to use the high heat anti-seize which sells for 8.00 for a LIFETIME supply.