A faulty mass air flow (MAF) sensor can cause erratic/rough engine operation and fuel economy issues. Since this sensor measures the actual amount of air entering the motor, when it fails, the engine control module (ECM) takes the wrong information and delivers incorrect volumes of fuel to the cylinders.
Erratic Engine Operation and Poor Fuel Economy Due to Faulty Mass Air Flow Sensor on Mercedes-Benz S420
Average mileage: 153,671 (109,000–303,498)
14 people reported this problem
I was told that My mass air flow unit is going bad. Is there any way to clean it or do I just have to replace it.
1995 Mercedes-Benz S420 141,326 mi, Visitor
veh had starting running rough and losing gas mileage can smell the strong ordor of fuel with white smoke coming out
runs poorly, with rough idle, has no power when driving. How often should I spray the sensor and or do I need to change wires?
Was getting engine fault. Cleaned sensor located in driver side air intake using CRC MAF Sensor Cleaner purchased at Kragen (now O Reiley Auto Parts). Cleared fault using LED/ Pushbutton feature (may not be available on all models). Works perfectly.
1995 Mercedes-Benz S420 165,000 mi, Visitor
I have a similar problem, especially when the car sits for a while without driving. I always keep a can of MAS air spray in my car. By removing the cover over the MAS unit, I spray a small amount into the unit; it works like a charm.
I HAVE THE SAME PROBLEM ITS LIKE THE COMPUTER HAS TO FIGURE OUT WHAT TO DO WHEN YOU HIT THE PEDAL AND ONCE IT RELISES WHAT TO DO IT GOES LIKE A ROCKET!
1994 Mercedes-Benz S420 303,498 mi, Visitor
Low MPG and terrible idle noises