I have a frst which will does not drive smoothly on part throttle.
if you drive below 50/60 mph it will stay off boost and perfectly smooth, up to 90 it will not drive smoothly. I went to stamford hall yesterday and cruising in the convey it was constantly showing boost of 3-4 psi and juddering. when it went above 90 it was fine. Managed only 150 to a full tank of petrol
spec is 2.0l zvh, kent cam, t3, stage 1 chip, 10 psi boost. any ideas welcome

 

over fueling mate , till it clears i guess .

ive got the same probs with my 2.1

yours drives mine doesnt , get it to a garage and see if the co is set correctly , 3.5 % at idle
also check out the fuel pressure 3.5 bar but cant rember if thats with the vacume hose on or off ???

last thing it may be is the fuel pump , or wiring breaking down but that doesnt tally up with the poor fuel consumption .