Menu#4 on my web page shows a 'graphical' Lambda of "1" (when it's at 0.45V) but, as you know, this voltage is sweeping from from top (0.8V) to bottom (0.05V), so it's continually changing.

If you measure Lambda on a 'd/c' meter, it should be 50%. . . at idle and at high rpm. The fact that it isn't could mean a lot of things. Missiing/fouled injector, bad plugs, contaminated O2 sensor, contaminated/failing MAF, and the list goes on.

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Regards . . . . JimF
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'94 S500 Cpe

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