1991 Mazda b2600 Repair Question
Mazda b2600 Spark Problem
check your spark plugs for oil fouling. the blue smoke is because oil is entering the cylinder (when it burns it gives off blue smoke).
This oil will foul the spark plugs and cause the engine to misfire and loose power. If a spark plug is oil fouled, it will black wet looking oil on its tip. Replace any and all oil fouled spark plugs and the engine should run better.
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