That car & all V-8' upto 1986 don't use a standard duty cycle signal.

That signal from the computer is actually a Hz frequency. We used a special "LAMDA" box to set-up that fuel mixture.

You can measure the O2 voltage & set the mixture by splitting that signal into half's.

__________________
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)
Retired Moderator