While Driving my Mercedes 400E about 80 MPH the Engine decelerated to about 60 MPH and I pushed further on the pedal and it went back to 80 MPH. After I got off my exit I was caught in traffic and had to stop. Once the traffic started to move I pressed on my gas pedal and I had to go about half way on the pedal travel before the car would move, then it would jump. After I got home I shut the car off and restart and everything was fine. I drove the car to work without any problems. However, on the way from work today the same thing happened. This car has regular maintenance done periodically. i.e new caps, rotor, wires, air filter and plugs. The oil was recently changed approximately 700 miles ago. Any ideas?

 

Are you getting any Check Engine Light? Even if its not showing this could be an indication of a MAF going out. Just a personal experience into the theroy on how everything works. If your MAF isnt sending air updates the engine doesnt know how much fuel to dump in. Normally you get sluggish response or Intermitent Surging during acceleration.

My fabricated an intake for my 2007 Chevy 1500 and didnt properly seal the section between the intake tube and the MAF causing extra air to flow in and I could barely get above idol, when pressing on the gas it cause the truck to nearly die.