Car shown intermittent problem of not accelerating when gas pedal is pushed. It will give many jerky movements but then after few minutes driving like this it will normalize. I took it twice to dealer and they could not identify or replicate problems. Then my wife taking kids to school has similar problem so I got scared for safety of kids and wrote to their head quarter. They told me to take the car back to dealer and leave it for 5-6 days so they can try to find the problem. After few days they gave me "great news" that they confirm the problem and identify the source it is"water in the gas" I was told that costco and smith sell cheaper gas but quality is not good and told me to watch" channel 3"where there was a report in this regard. I told them that I don't buy this theory as costco and smith are two big companies to allow this lacking and I see thousands of other motorists getting their tank filled there. They told me that mb will not guarantee until gas has not changed and I agreed to change the gas and get later fill up from "chevron".or the safety of my kids I still follow their recommendations and gas is only refilled from chevron but as I suspected this is not the problem as car continues to have similar problem and will not speed up by pushing accelerator intermittently. Due to risk car is almost kept in garage and used only for intense need.

- Henderson, NV, USA