HBsurfer

I changed the plugs on my wife's S series Mercedes at 88,000 miles and they came out easily and did not need changing. The car was 9 years old at the time. Unless you just want to play around with your car (something I am guilty of), don't even pull one to look at it if your car is running ok now.

important

I did but therye not DIYers like Vette people.

I would trust the guidance I get here over any other forum.

important

Gawd dayum, 88kmi and 9 years and still good to go.

Woo hoo!

This is the answer my scared *** was looking for.

I'm just gonna let em ride, should be fine.

Any difficulty removing them?

HBsurfer

No problem at all removing them. I just like playing in the garage so I did it. Car ran fine before and after.

RPOZ4Z

CMY SIX

do not put any thing on the threads, as there is already from the MFG. if you look at the box most of the MFG's say do not.

Weasel

I just changed mine 3 weeks ago at 36000 miles for something to do. No improvement.

Not So Fast

Todays plugs have a compound already on them, I called a few of them to confirm this so no anti-seize they said.
I still put a tiny dab But be very careful when installing about cross threading
NSF

User Omega

Don't do that.

Cherokee Nation

LowRyter

I'd find a reputable repair and maintenance shop.

important

Mercedes quoted me $900 to do the job... hahaha

Although it seems like damn near any place (even a Pep Boys) could do the job with ease.

But I would like to do it myself just because it does seem straight forward and I prefer to not let others near my car.

important

One site recommended that the spark plug gap be checked before installing.

Despite coming "pre-gapped", apparently the gap can change due to shipping, handling etc.

Are the gaps specific to the plug or the engine?

I ordered the Bosch Double Platinum YR7MPP33.

On their website, they are calling for .8mm with this disclaimer:


https://www.boschsparkplugs.net/product.aspx?zpid=8298

"Most manufacturers set the gap from the factory for that plugs most popular application.

Unfortunately, that plug may have hundreds of applications from automobiles to golf carts.

Setting the gap for your particular engine is important as insufficient spark plug gap can cause pre-ignition, detonation and even engine damage.

Even if the preset gap is supposed to match your motor, it is always best to physically check that the gap is adjusted properly for your motor prior to installation."

User Omega

I suppose that I am missing something? Why are you changing the plugs at such a very low mileage?

Kenny94945

FWIW I recall plugs have both time and mileage.

In your case:
1) I would only inspect the plugs not replace (as plugs have near 100K mileage life).
Insure they "read" okay, no pucks on the plugs have disappeared from the electrode, verify gap, verify insulator tip is tight.
2) 5 yr time it is good to remove and reinstall (w/ anti seize installed) to break any potential bonding between aluminum and steel.

Take extra care with your plug wire during removal and utilize di-electric grease upon re-install.

If you are not able to DIY this, I would not have the dealer do this and just enjoy the car until more miles accumulate.
Later deal with any issues as I doubt new plugs will offer the OP any performance, fuel, etc gains at this low mileage time.

Good luck, many great answer above.

NJ_phil

I pull my plugs every time before I hit the track or do an oil change and use never seize but be sure not to get any on the last 1/4" of the threads which are exposed to the combustion chamber.

Most noobs, not saying you're a noob, run into more problems with putting the plug wires back on correctly

windyC6

At the relatively cheap cost of spark plugs. If after 5 years or so i'm spending the time to remove them, i'm not gonna stick the old ones back in. Might as well put new ones in.

Mad*Max

But you will need to change the wires while you are at it - I have had many professionals say not to put the old wires back once you have pulled them.

mikeCsix

Lots of opinions regarding the use of anti-seize compound on the threads. If You do, you will alter the torque characteristics of the install, over tightening the plugs by reducing thread friction. Use of a torque wrench on aluminum heads is highly recommended, a quarter turn beyond finger tight isn’t accurate enough.

Boots tough to remove at 100k miles is also an issue and probably what prompts the comment regarding plug wire replacement. Wires are generally not copper wire, but a carbon filament easily damaged by too aggressive handling, such as boot removal. Try tying an old shoelace to the plug boot for extra leverage without wire damage.

And yes, gap should be checked. Inexpensive wire type plug gap measuring tools are easy to find at the auto parts store. Don’t use the round disks, they are not accurate enough.

Mike's LS3

Not on AC or NGK plugs, they already have a dry coating on them. The coating helps resist against moisture and chemicals. Adding anti-seize coating will act as a lubricant and may cause inaccurate torque readings which can strip spark plug threading.

As far as the OP, on a stock application wait at least 50k miles before replacing the spark plugs.