Also suffering from an idle problem:

Starts and idles okay from cold, but once I've been driving and come to a stop, the revs rise to about 3500 rpm then drop back down. This happens when cold or hot. It is a slow and gradual increase to 3500rpm not a sudden rise, takes a couple of seconds.

My first thought was sticky ISCV? Maybe TPS?

Have had a quick check and found no air leaks.