The car fires right up, idles smooth, and sounds great. However, when I press the pedal to around 1-2k, keeping the pedal in the same position, the engine speed varies 1-2 hundred rpm. Not only does thsi happen when I'm sitting still but also when I'm moving, causing the car to jump, and jerk like it's about to stall. If I adjust the TPS sensor it fixes it, but only temporarily. Any help will be greatly appreciated.

 

Not sure if this helps or not but I had the same problem on my pickup truck. I swapped out the TPS sensor and it fixed it slightly. Turns out it was the wiring to the TPS sensor that was the problem.