Volkswagen Repair: 2000 vw jetta boggs down and bucks, mass air flow sensor, mass air flow

Question
i have a 2000 vw jetta 2.0 and if i barely touch the gas it accelerates ok, but the further i push the gas, the engine boggs down.  it won't seem to go over 4000rpm and bucks and boggs down while going down the road.  I have replaced the fuel filter and plugs, any help would be appreciated.

Answer
Don, thank you for your question.  Sounds like one of the sensors dealing with the fuel injection or fuel flow is not working right or damaged.  The problem could also be the MAF (Mass Air Flow) sensor, throttle control or the EGR valve.
Hope that helps