got a cheapo micra k11, when trying to hold the speed at say 20 or 30, its like a constant jerkyness, its doing my nut in, its like your going up and down with the throttle...

anyone know what causes this and what to look at, air filter looks clean , spark plugs look ok etc ive cleaned the throttle body out, wiped it etc etc..its a throttle with cable engine if that helps, would ask on the micra website i joined, but useless on there.

cheers