o2 problem.
I burn no oil either and i`m using Motul 8100 5W-40, relativily thin for average temperatures here. Engine has 126.000 miles and still is like new. Actually had it mapped this week and the tuner was surprised to see such a healthy engine keeping a clean A/F ratio and didn`t stink burned oil on the dyno.
People who say they use no oil are either lying or not using the engine
People who say they use no oil are either lying or not using the engine