tongster

ok, this is a stupid question...but i'm in the process of changing the spark plugs in my 99' ML320. I thought it was only 6 plugs but it looks like more (maybe 12?). Can someone help me out with this? I'm currently working on the driverside plugs first and noticed that there are 6 plugs that I can remove. Do I replace them all and then go on to the other side?

Thanks!!

saturnstyl

Yep, 112 V-6 has 12 plugs, 18 valves.
113 V-8 has 16 plugs and 24 valves.
137 and 275 V-12 have 24 plugs and 36 valves.
All others only use 1 plug per cylinder. Most others use 4 valves per cylinder also, instead of 2 intake and 1 exhaust like the above motors use.

tongster

Thanks, I figure that was the case. First time I ran into this.

benzboy

Make sure you relpace 'em all - both sides!

tongster

Thanks! I just did the driver side so far and didn't have time to do the other side, but will go at it this weekend.

saturnstyl

Its easier if you pull the front wheels and plastic fender liners out. You get almost a straight shot at the plugs through the fenders.

STi_JL

BIG question ..
i need to know how to change plugs on a ML320

mercedes in BC wanted to cahrge me 1600
and they say the only problem is plugs ..so i decide to do it my self..
please help .. thanks ....
can i ahve the spark plug # too
damn .. 1600 .. my car wouldnt move too .. and it sooo slow .. did this happen to any ML users and the proble was plugs?

benzeboy

Search the forum there is several excellent write ups on changing spark plugs.
I 've used it to change mine. you might want to check your air filter and maybe change your fuel filter to solve the other problem. Good luck
I used bosch platinum III. Working great for me.