Hesitation

[olly_mango]

My car started to hesitate slightly when accelerating sometimes and then quickly developed into doing it all the time, there doesn't appear to be any pattern to it at all either, its all over the rev range. I've tried a coilpack and map sensor on it and neither made any difference. It only had new plugs and leads in january. I've also tried swapping my bosch lambda sensor I replaced in january back to the original, but still seems exactly the same. Any other ideas of what I can try next or what it could be please?
Thanks

 

[Karashi]

Try cleaning the throttle body.

 

[olly_mango]

yeap, had it all apart and cleaned it all out.

 

[olly_mango]

Just unplugged the pre cat lambda (I only run with one lambda plugged in anyway, as I have a decat) as I had a thought it maybe that after I did some more searching and it seems to have semi sorted it, as if I boot it on full throttle I dont get any hesitation, but if I drive normally then I get a very slight hesitation at around 4k? Maybe a new lambda would sort it?