Toyota Repair: Toyota miss, maf sensor, 7l

Question
I have a Toyota with 2.7L engine and first the check engine light came on, test showed O2 sensor..reset and engine running fine.. after few hundred miles the check engine light came back on and also now sometimes will miss a few times while driving 50 miles...Cleaned the MAF sensor with electrical cleaner..than only missed two times in past three days....Is the MAF bad or maybe the O2 Sensor..Thanks

Answer
If it has an engine misfire then it should store a misfire code in the computer, can you let me know what the trouble codes are, most of the larger autoparts stores will get the codes at no charge, let me know what he codes are and also what year and model it is.