I've seen alot of airflow meters bite the big one!
Test it with an ohmmeter as follows, center pin is common,measure between common and pin one while slowly depressing air sensor plate,the reading should change throughout the movement of the sensor with no major open circuits(threr is usually one halfway down)
Next measure common to pin three and look for the same results.
I don't remember airflow meters causing high idle like you describe.
The answer to the last question;yes you may have other codes as well!