P2096 code

Question by Elie Ghanem posted 6 months 2 weeks ago in C-Class

My MB c240 has thr trouble code 2096 when i check the live data i see all the fuel trim long term and short term in both bank are negative they reach -9./. Which mean the system is rich but the code 2096 give me post cat bank1 is lean why this contradiction ?
I hear all time a siffering sound from the engine