S 550 (221.171) V8-5.5L (273.961) (2007)
Lambda control loop
Assuming a leaner air/fuel mixture is produced. The consequence of this is that the O2 sensor voltage drops and the ME-SFI [ME] control unit
compensates for this lean drift by enriching the mixture accordingly.
This makes it possible to achieve an air/fuel composition of approximately (Lambda) =1. The reading of the lambda control factor with the STAR
DIAGNOSIS moves towards +25% The more the lambda control factor moves towards +25%, the leaner is the air/fuel mixture and the greater is the
enrichment of the mixture on the part of the ME-SFI [ME] control unit.