[Wayne 962]

I would double down on the search for a vacuum leak. The code 1222 is not an oxygen sensor problem, but it's detecting a mixture problem at idle, which is very often caused by a crack in a vacuum line. Double check the intake boot - these crack all the time and you can't tell until you squeeze them. I had a problem like this on my 318 - there was a huge crack, but it didn't show until I squeezed the intake boot.

-Wayne