Yep the MMT caused the plugs to foul and this overstressed a few of the coil packs causing them to arc in well....................self inflicted damages.

 

What's does "MMT" mean?

 

MMT = Methylcyclopentadienyl manganese tricarbonyl is an organometallic compound with the formula (CH3C5H4)Mn(CO)3. Marketed initially in 1958 as a supplement to the gasoline additive, tetraethyl lead to increase the fuels octane rating, MMT was later used in unleaded gasoline

 

Yes, Sir. Nissan made that point clear to me that is exactly what happened. "self inflicted" damages.
Quite an expensive lesson I learned from all of this. I feel like a complete idiot since the bottle of Octane booster even has a warning on it that it is not meant for cars with O2 sensors and catalatic converters. I should have known better. I just hope my mistake can be a learning experience for others.

as far as the cost...it was for the plugs, coil packs, ECU flash, and labor. I also had them flush and replace my tranny fluid and engine coolant since it was already there, thought to go ahead and do some of the other maint. items.

 

That sucks. One expensive lesson.