I was wondering if anyone could help me, as I have no idea what's causing this. When accelerating, in third gear, at around 3500rpm the engine seems to suddenly hold back, and then carry on. It doesn't do this in other gears. The MAF was replaced just over a year ago. I've also blanked off the EGR valve, again just over a year ago, and haven't had any problems so far. What do you think? Any comments would be appreciated.