Self-adaptation of mixture formation to limit, fault code description ME-SFI - AD07.61-P-4000-09A

1	Fault code	P0170 right cylinder bank P0173 left cylinder bank
2	Fault storage	after expiry of test duration and fault
2	Actuation of the engine diagnosis indicator lamp (EURO3/4) or CHECK ENGINE (MIL) malfunction indicator lamp	after two successive driving cycles with faults
3	Checking frequency	continuous
4	Checked signal or status	Self-adaptation of the mixture formation to the limit value
5	A Idle speed limiting value	approx. ± 1.0 ms, additive correction (corresponds to approx. 25 % of the injection time in idle speed)
5	B Partial load limit value	Factor of 0.7 to 1.3, multiplicative correction
6	Check prerequisites	Coolant temperature > 80 °C Catalyst temperature > 380 °C Lambda control enabled No fault in catalytic converter effect No fault in O₂ sensor heater or aging Air pressure more than approx. 780 hPa (i.e. no test is performed above a height of approx. 2500 m)
7	After a repair, carry out tests and driving instructions	The tests 1 to 4 must be carried out together one after the other without switching off the engine. 1st Check O ₂ sensor heater Vehicle is stationary and in drive position P Coolant temperature > 80 °C Let engine run at 2000 up to 2500 rpm for approx. 2 minutes Then let engine run in idle for approx. 6 minutes 2nd Check aging of O2 sensor upstream TWC [KAT] Drive vehicle in drive mode D for approx. 3 minutes at approx. 70 km/h on a straight road 3rd Check catalytic converter effect Drive vehicle in drive mode D for approx. 3 minutes at approx. 80 up to 90 km/h on a straight road 4th Check self-adaptation of mixture formation. Vehicle is stationary and in drive position P Let engine run in idle for approx. 3 minutes If the individual test is performed, this is displayed in the HHT as follows: If the test is passed without a fault, "-V-" is placed in dark (repair is successful). If the test is passed with a fault, "-F-" is placed in dark. After ignition OFF the tests are again restored (white field). Only after the test has been performed once again, the corresponding fields are once again placed in dark. Carry out a new test only after approx. 10 seconds ignition OFF.

Self-adaptation of mixture formation

Fig 1: Identifying Self-Adaptation Of Mixture Formation Graph

Courtesy of MERCEDES-BENZ USA