MAF or throttle position sensor problem?

I have a manual 2000 vr6 jetta. A few months ago I got my throttle body replaced. Since then my check engine light still has not gone off...Taken it to the shop 5+ times and each time they fix something....i drive away from the shop and my check engine light comes back on. The problem is.... when driving if my rpms are over about 2600, and im keeping at a steady speed, the car starts to feel like its pulling. Kind of hard to explain but it feels almost like my car is trying to speed up on its own. When I'm speeding up or giving it a good amount of gas then it doesnt act up. So when I'm driving on the freeway in 5th gear...the fastest I can go without my rpms getting over 2600 is 70 mph....quite annoying. If I drive for a while over 2600 rpms, the epc light comes on, the traction control light comes on and it says emissions workshop. Then that will go on and off until I shut off my car. I've had a few friends suggest the MAF or throttle position sensor. Trying to find out any extra info I can before taking it back to the shop. They've also already replaced the 02 sensor so im assuming thats not the problem..

Hopefully that explains well enough, any information would be great. Thanks!