Catalytic converter replaced to correct sulfer smell problem
Engine idler pulley bearing was loose causing high pitched noise. Dealer replaced pulley.
#4 piston was leaking oil causing oil to burn in combustion. This lead to excessive oil consumption, sulfur smell from cat convert, rough idle, etc. Toyota is aware of problem and replaced piston free of charge even though out of warranty.
Cat converter was changed due to excessive sulfur smell. There was a TSB on this issue.
Check engine light came on but went off. Could not diagnose issue. Still doing this 2 months later. Only goes on for a day then back out for a while. No running issues. I think a coil is going bad. Update: light later stayed off, fixed itself.
Replaced the downstream 02 sensor after a Check Engine came on