so what does it actually do when u put it in ur oil? does it burn off some of the carbon? also how much does a mazda thermostat cost at the dealer? i have a freakin discount auto parts one and i think it keeps gettin stuck, cause i boiled the coolant the other day when i go home from a 15 min highway drive. car didnt overheat though. and it wasnt missin alot of coolant. sound like the thermostat to you guys?

 

Do a search, theres a thread about MMO about ever week. Basically, its great stuff, and I use it every oil change. It dissolves any deposits in your oil system, and is good for the engine bearings.

New thermostats are $22 new from Mazda. Worth every penny too. Go get one right away.