Gino

I've read in the Bosch Engine book that CO-mixture can be checked by the lambda sensor (O2 sensor) with a dwell meter set to 4 cylinder and a reading of 45% will indicate a correct mixture.

but where is the duty cycle test terminal?

I understand with this procedure, one can adjust the mixture setting (counter to lean, clockwise to richen). I don't have a gas analyzer and this seems to be a good tool as a troubleshoot to see if a really rich, or lean situation exists.

has anyone done this?