Rough idle, acceleration is delayed, studders a lot and won't go in reverse

I replaced the "Idle Air Control Valve" with one that I found on an old golf about 6 months ago and that fixed my idle problems. I also replaced the "fuel pressure regulator" and that gave me my responsiveness back in the acceleration.

But the problems are back. I turned the car on and unplugged the "IACV" and the car continue to idle. Shouldn't unplugging that kill it?

The hoses connected to the IACV have small stress cracks but I don't see how it would cause the car to run that rough?

It may be bad fuel as I have gotten that SEVERAL times before. But it is just stressing me out.

The car also won't go in reverse (manual). My buddy says I should replace the shift bushings inside the car.