What Causes Overly Rich Air-Fuel Mixture in Cylinder Banks 1 and 2 of Mercedes-Benz?

[Carolyn]

This malfunction is caused by two reasons: one is intake air leakage, and the other is a damaged air flow meter. The solution is to check the adaptive values. If they are below the lower limit, first test for any air leakage. Methods such as plugging leaks or spraying carburetor cleaner can be used for detection. If there is no leakage, it is recommended to replace the damaged air flow meter. If there is leakage, the leaking part needs to be addressed. The manifestations of an overly rich air-fuel mixture in the engine are as follows: 1. Symptom one: Gasoline leakage can be seen around the valve shaft when the mixture is too rich. 2. Symptom two: The engine lacks power and is difficult to accelerate. 3. Symptom three: Black smoke is emitted from the exhaust, accompanied by a "popping" sound. 4. Symptom four: Excessive carbon buildup on the spark plugs. 5. Symptom five: In severe cases, the engine may stall automatically and fail to start.