JAD

My 1999 ML430 has about 50,000 miles on it. Last time I had a service performed, the delaership told me that the plugs need to be changed. The vehicle has less than the 100k on the odometer that the manual states for plug changes. However, the dealership told me they should be changed every 4 years and that they would do it for the modest price of $550+. The truck seems to be running great so I have 2 questions:
1. Do they really need to be changed with less that 100k on the odometer?
2. If yes, can I change them myself? Is is a difficult job? Has anyone on this site perfomed this job themselves?

Thanks for any insight!

Justin

ML God

I have....it's not very hard....the wires are an absolute ***** to take off unless you have the MBZ special tool. You remove the coils with the wires then you replace all 16 spark plugs (2 for each cylinder)

JAD

Is it necessary to remove the wires to get the plugs out? How long should this job take for someone with decent mechanical skills? Thanks.

ML God

Yes you have to pull the wires off the plugs so you can get the socket on them...taking your time maybe 2 1/2 - 3hrs we get paid 2 hrs to do them. it usally takes me about 1hr and 5 min!

Stiggs

Lets get to the first question.....do you really need to replace them. My Ml is a 1999 and it has about 43K miles on it...are mine going to go soon? I should hope not....you think spark plugs on a benz would last longer than 50K miles. I didn't have to replace the plugs on my 1989 mercury sable until it had over 100K miles!!

ML God

It's really up to you...it's not like they are all going to just go out. if one get fouled you will feel a miss fire and lack of power. it's just good practice to keep up on all your preventive matience. in the long run you will get better fuel milage and better emissions. If it was up to me i would change them...we get a lot of ml owners that when it is time for there service they decide to have us change there sparkplugs...so go for it!

randyman

i'm a DIY person. how do i take the engine cover off? do i just pull it out? screws? does HELM's have a manual for these trucks?

cheers!

ML God

Yep it just pulls off, no screws...just be carefull they break easy

randyman

SUPER!

8^D

ML320AMG

dear ML god,

I just bought 12 NGKs from importec.com and could you please tell me how to remove the plug wires (turn ccw?/pull the boot) and the coils

If thats too hard for DIY person ... can you slip me the part number for the special tool?

thanks.

Dennis

ML God

The wires just pull off. Try using an open end wrench just big enough to fit over the wire caps, then pry off. Good luck, the firt time they are pulled can be a BI#$H

ML320AMG

that goes with the wires ....

what about the coil pack ... should i remove that too to make life easier? how?


dennis ... with million thanks

ML God

Yes remove the coil packs. leave the wires attached to the packs. there is only one torks bolt holding it on