amgalex

What you guys think?
Is this normal wear or what?
this is how all of my spark plugs look.
2000 e55, 106,000mi, had maf issue check my other threads.

Plugs have Mercedes logo on them, so I assume they are original

vettdvr

The gap looks burned wide missing the platnium tip.

You didn 't indicate a measurment and compare to spec or indicate total miles.

They look dark almost black on the insulator which indicates rich or cold. You might be running fuel rich due to o2 sensor malfunction, assuming you aren't using oil. You also didn't mention is your fuel economy down or any check engine lights. Given no check engine lights and fuel economy the plugs look cold and burned on the electrode. Do you have the correct plug as recommended in the owners manual.?

RobertG

It looks like it's running a bit rich, but it looks ok to me.

mleskovar

Looks too rich, but hard to tell from picture angle. Threads also look oil coated, not good. Electrode looks like its being eaten away, not common with today's engine management systems and no lead gas. How does the car run?

amgalex

When I bought the car it was as quick as my gf's e320 so around 120hp less than it should have , got new maf, did a battery reset and whala power is back although over time car becomes slower again so resets are necessary pretty often. Check my other thread.

mleskovar

The picture you just added says a lot....that looks terrible. If it's not running too rich then it's oil fouling to be that wet. The deposits are probably oil byproducts. Does it use oil? Does it give a puff of smoke when you start it? Does it belch smoke when you nail it?

amgalex

no burning oil,, no smoke
but car was running like crap before so that i think explains is
here is what i found that i think is the cause on spark analysis page
"
Splashed fouling, , may sometimes occur after a long-delayed tune-up. Here, deposits accumulated after long periods of misfiring or low power operation may be suddenly loosened when normal combustion temperatures are restored after a set of new plugs has been installed. During a high-speed run, these materials shedding off the piston are thrown against the hot insulator surfaces."

this sounds like what happened to them because i was down like 120hp before maf

softgenious

Those plugs look like they do because they should have been changed a long time ago. Once plugs brake down, they will not function like normal plugs in good condition. I would replace and check in 5k miles.

grigore

I think the same as softgenious!Those spark plugs have to be changed, they have too many miles of hard working...

amgalex

Mercedes recommends 100k mi intervals for spark plugs, so that probably way too late.
I wonder if this applies to the 10,000mi oil change?

Gullwing

Replace plugs every 5 years or 100,000 miles for M112/M113 engines, but I am not sure if it is different on AMG engines.
Replace the plugs and reset mixture adaptations.

If the engine has missed basic repairs, what about the transmission, suspension, coolant, and other fluids? I would go over and replace all fluids just to be safe. Do a few quick engine oil changes, change and drive 5K and change again...

softgenious

You are maxing them out at 100K. On any engine, I would pull them and check at 50K then every 25K until I decide to change them out. Most, even if they are platinum need to be changed after 75K.

amgalex

by the way these spark plugs are NGK R with a Mercedes logo so I assume they are from factory. Anyone have experience with these plugs?