I had that miss before. Tried a new OEM O2 sensor. Helped for a while, but it came back. Finally got rid of it for good now. On mine, it turned out to be an exhaust leak. Air entering exhaust diluted the exhaust gas and gave O2 sensor bad reading.
Last stud on cylinder head alwayst tend to strip or loosen. On stock car, the joint between exhaust manifold and down pipe always loosen on a regular basis.
Both those problems are because there is no flex pipe in the stock Toyota exhaust. After a flex pipe, new exhaust studs and stage 8 permanent locking fasteners on the joint, the miss is gone for good now.