my car was running good for the last 700 miles without any codes after solving the problmes with the last codes that i had. anyway, i was on my way home today when i saw the CEL come on... when i got home i checked them and came up as P2196 and P0300 p2196 is a code that says the o2 sensor is stuck rich or something i think from what i searched and p0300 is multipule random cylinder missfire. i was wondering if anyone could help me figuring out why im throwing these codes?car didnt feel like it was missfiring today when i was driving it, i didnt hit boost at all today while i was driving.i was thinking maybe the o2 sensor is bad, but how do i check for that as they can be pretty expensive i was looking at this thread: https://www.scionlife.com/forums/vie...p0300&&start=0

that seemed to be his problem and those were the same codes more or less that he was throwing. any help would be greatly appreciated, thanks