1993 NAS Defender;has a jerkiness/missing always between 2600 and 3000 rpm.Never there at lower revs,disappears as the revs drop or increase.In all gears,hot or cold.

Distributor cap and rotor is relatively new and looks good, plugs and plug wires are new. Fuel filter is 1year old. Coil is 10 years old. ignition module is 11 years old.Everything else original.

Any ideas/help please!!

Abraham