the 190E 16v supplement engine manual http://mb.braingears.com/201_DISK1/PDF/40001a.pdf
talks of the CIS reverting to a fixed operating mode if any of the sensors stop working or short circuit etc.

It would seem to me like a good idea if there was a way of knowing that it was doing this...

Is there some obvious sign or test?

Russell

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190E's:
2.5-16v 1990 90,000m Astral Silver
2.0E 8v 1986 107,000m Black 2nd owner
http://www.maylane.demon.co.uk/190esmall.jpghttp://www.maylane.demon.co.uk/190esmall2.jpg

I should add, this is a Euro 1990 16v without any lambda/O2 sensors or any of that malarky.. so I don't think I can measure the duty cycle .

Russell

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190E's:
2.5-16v 1990 90,000m Astral Silver
2.0E 8v 1986 107,000m Black 2nd owner
http://www.maylane.demon.co.uk/190esmall.jpghttp://www.maylane.demon.co.uk/190esmall2.jpg

The US 16V versions had FOM but no diagnostic ability!
Starting in 1988 either the duty cycle signal at pin 3 of the ROUND connector or pin 3 of the 8 pin diagnostic connector should provide that info!

__________________
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

Russel,
I wouldn't call it malarky. Without Lambda control, you are driving a basic CIS system from the dark ages. Unless Bosch has produced an exotic system just for England, you are driving a car with 1976 technowledgy.

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