Misfires under load (acceleration) can be caused by leaky spark plug boots. When a spark plug boot leaks, it allows the spark to arc, or jump, to the cylinder head. New spark plug wires will be needed.Google+
Car Problem Reports
Mazda 323 Misfires Under Load
Mazda 323 Problem
Engine Affected: 1.6L 4 Cylinder
Visitor, 1992 Mazda 323, 1.6L 4 Cylinder, 225,000 mi
Engine misfires mostly under load but today it is doing it in idle to the point of shutting off. It seems, it is doing it more after being not driven for a while, at least over night or week-end, or rain. Can it be due to humidity? It feels like after a while that the car is driven, it dries off and then it is fine until the next time when it is not driven for a few days, or it rains.
No resolution yet.