What do you think is causing the first three codes

Why no details? Can you give us more background info? How many miles on the car? Did these codes show up recently? Or is there a chance they've been sitting in there for a while? Did they come back right away after you cleared them?

In general this could be as easy as a bad tank of gas and problem goes away once that gas is gone... OR it could mean your engine is not burning fuel efficiently / in a clean way and is in need of a tune up or other repairs? What's the service history?

We aren't mind readers... You gotta give details if you wanna get details!

 

They could definitely mean the sensor voltage read as > 0.59 volts when the target air-fuel ratio was lean, or that the sensor voltage exceeded 1.2 volts under any conditions at all, for 10 seconds or more. Either would have had to happen on two separate trips.

The troubleshooting steps for all four codes P0136, P0137, P0138, P0139 are all combined into one 38-page section of the 2010 repair manual.

Toyota Service Information and Where To Find It | PriusChat