before valve cover repair engine idle was rough , repaired leak ,changed spark plugs,wires & coil pack. the location of the oil leak is the cylinder that has been the problem. lifter sounds a little loud also on this cylinder , could the ignition control module have gotten ruined from this leak?
will valve cover leak into spark plug hole ruin ignition contol module on 1992 Mazda Miata MX-5
Oil leaking past the spark plug tube seals in the Miata Valve cover often causes plug wire failure and or a misfire. I don't think the control module would fail. Try using the engine oil additive Risolene each of your next few oil changes see if that helps clean the hydraulic lifters.