For those of you that don't know, the tune up has been gone in Mercedes terms since the mid '70's. Those were the days when mechanics DID tune-ups all of the time.
The reasons were simple. The engines back then used crude fuel management methods and crude but effective spark management. The points, condensor, spark-plugs and even the cap and rotor might be worn out in as little as 12,000 miles or so.
Now days, we have highly sophisticated fuel and spark management that allow the service interval to be quite long.
The engines don't have distributor caps or rotors since '94 or so. Instead the coil(s) are positioned on top of the plugs. This takes out much of the wearing items.
If you follow the E and EZ, or the A and B service schedule as outlined, the need for Tune-ups will be no more.
(In my opinion, if some one comes in asking for a tune up on a newer car, they haven't serviced it and it is skipping due to worn spark plugs 90% of the time)
Thanks for viewing my VENT.
ASE CERTIFIED MASTER AUTO TECHNICIAN
MERCEDES SPECIALIST 11 YRS