i have done the pcv, plugs, wires, gas filter, oil and filter, air cleaner, i put the NGK Iridium IX Spark Plugs and i still getting 12 miles a gallon i am putting in seafoam today do you know of anything more i can do before i put it for sale i cant aford to drive it i put 100 miles aday costing me 25 bucks a day HELP |