Captshine

This is my first post, so forgive me if this has already been covered (I tried finding this subject but didn't find anything).
The "Check Engine Light" comes on about once a week with the car driven almost daily. With a professional scanner/reader (a Snap-On Solus and good mechanic using it), it shows codes 0440 followed by 0460. When the technician checks and activates every sensor or circuit associated with these evap codes, they all respond normally and it shows that the engine passes the test. I'm just repeating what the tech tells me-I don't know a thing about this except I trust him. But, and this has happened 3 consecutive times, when the "ghost codes" are cleared and all is well, the VSC, VSC OFF, and red Warning Triangle illuminates all come on when I start the car right afterwards and pull forward less than 10 feet.
For some reason, when the codes are cleared, it throws off the Steering Yaw sensors and triggers the warnings. Once those are reset to within tolerance, the lights go out and stay out until the "Check Engine" codes are cleared again!
I have no idea what to do. The tech said if the C.E.L comes on more frequently, I could have a smoke test done to see is there's a very small leak somewhere, but yet all the EVAP components show they work perfectly.
Thank you so much in advance for any and all advice, ideas, or suggestions. Our LS has 229,000 miles on it and still runs like a dream.