16V engines had timing chain tensioner problems until the 2.5 engine came out in 1988. The chain can jump 1 tooth & still run but will not have any real power.
The cam gears each have a timing alignment hole & they will align at TDC.
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)