You never mentioned before about the hunting, now that I know this I would say the TPS is at fault, exactly as said above about the wear spot, this usually shows itself when driving in traffic as well, these are ok when the throttle is above this point as obviously it moves past the worn point.

PF01 TPS is a potentiometer with a switch so with no throttle it is open circuit, it should read around 0.5V at WOT obviously giving a higher valve up until 5V of course the further closed the throttle is. Check between pins 11 and 17.

Easiest way to test is with it still on car, from the ECU connector (You may need an assistant to operate the throttle while you use meter) although is do able by yourself.

Martin