hey i have a ba xr8 and at around 1500 rpm in some gears my car surges. im leaning towards a fuel filter problem cause it only does it occasionally.

just want to know has anyone else got some other ideas, ive changed petrol stations to see if its just dodgey fuel but its not... and if it is the filter where is it i have a manual for the B series falcon but it doesnt outline where on the vehicle it is...

thanks any help would be good...