The injectors won't in themselves cause a high idle. Cut o-ring, possible but you would have had to really force it in to cut it that bad. As mentioned IAC do some pretty weird stuff, sometime you bump them and they get stuck. If you are sure you don't have a vacuum leak, try removing you IAC and clean it with some brake cleaner then spray some WD-40, tap it a couple time and reinstall it. Disconnect the BAtt before you turn on the key. You can also use water to find a vacuum leak.