Yes you do need to have the valve clearance adjusted!!
THIS isn't a simple job & you will need MANY valve adjusting shims to correct the valve clearance.
MOST shops DON'T have the ability to do this adjustment!!
MERCEDES Benz Master Guild Technician (6 TIMES)
ASE Master Technician
Mercedes Benz Star Technician (2 times)
44 years foreign automotive repair
27 Years M.B. Shop foreman (dealer)
MB technical information Specialist (15 years)
190E 2.3 16V ITS SCCA race car (sold)
1986 190E 2.3 16V 2.5 (sold)