Abstract: An engine ignition advance correction device in which a distributor co-acts with two independent capsules sensitive respectively to variations in pressure at different locations in the engine, the capsules acting on an advance lever pivoted on a fixed part of the distributor and carrying a pair of pivotally mounted advance levers, the capsules acting on the advance lever either successively to provide ignition advance when the depression is sufficient at only one of said locations, or simultaneously to provide ignition advance corresponding to the sum of the maximum advance values effected respectively by the capsules.