q1

car runs really well when driving normally!

q2

it did have a tps set up issue this is now sorted so the iscv does not effect idle when hot.

the only time i really notice this problem is at idle, the car is surging as its so weak(as you descibed the rich cylinder is fooling the lambda sensor)
i cant richen the mixture above .45% if i unplgg the lambda and adjust the mixture to say 1% its perfect... so this tells me the fault is purley a mixture related problem? its just to weak to idle nicely