do i need to buy some kind of engine cleaner to clean the inside of my engine? I can hear poofing noises from my muffler, i know its not backfire. my wires are in the right place. first it is every like 5-10 secs. aprt. now its startin to be just poofing noises. its getting worse! i had the car for like a year now and i havent done any major work just oil changes oh an timing belt and water pumpy!

 

Seafoam is safe to use in the crankcase aswell as a top end cleaner.