tuning an m278 CLS550 in 2024




If the car is coming up on one of the regularly scheduled services that includes replacing the spark plugs, do that a week before or after the tune, not at the same time; if something goes wrong (as it did for me during a recent plug change) it might be difficult to sort out if the tune is corrupt or if something else that was done at the same time is responsible.
FWIW, my 2014 550 had approximately 30k miles on it when I installed a tune, with standard maintenance before and after at the scheduled age/mileage intervals.




If the car is coming up on one of the regularly scheduled services that includes replacing the spark plugs, do that a week before or after the tune, not at the same time; if something goes wrong (as it did for me during a recent plug change) it might be difficult to sort out if the tune is corrupt or if something else that was done at the same time is responsible.
FWIW, my 2014 550 had approximately 30k miles on it when I installed a tune, with standard maintenance before and after at the scheduled age/mileage intervals.



