ttaunton

Thanks for the info. Mine measures 0.9v with the throttle closed, which agrees with your figures, within realistic limits. I went out this morning and started it, and within a few seconds the revs started climbing towards 4k. I went and got my meter and the centre contact measured 0.89v. ( I did it by sticking a needle through the wire to contact the copper inside) That proves, really that it probably isn't the pot, although the best test would be to disconnect the plug from the pot while the fault is on and see if the revs drop. Could the fault lie with the idle speed control valve? Is resetting the engine management system going to do any good, or is that something you should avoid?