Help needed please.
My 3 dr has had a misfire for a while now and its getting me down. It happens at the same place in the rev range (2100rpm) in every gear if i accelerate normally when the car is warm. It dosnt do it when the car is cold. The car gives a sort of cough and the rev counter will jump about wildly. If i put the boot down a bit it will power through and not misfire. On release of the throttle to let the car slow down under its own steam it gets to the said point in the range and the car will surge forward for about a second. Ive changed the crank sensor, plugs, leads but its still the same. Once again it only happens at 2100 rpm.

Any help will be appreciated, im no mechanical genious but i can understand the basics.