Correct. The clutch would chatter when the rpms would dip from around 1k to 500/600ish upon cold startup at idle. It happened for the first time on Sunday. I have only driven it twice since so I could get it back home. Chatter occurred both times. Rev the engine or push in the clutch and the chatter would disappear. Now it's perfect again. I have heard of other stock zhps chattering too.
I had 8 codes pop. 6 misfires and 2 lean bank codes. Once I saw the hole, I had no doubt that they were from the intake boot. I got the same codes months ago before I replaced the lower boot. (it wasn't big enough to mess up the idle though)