The previous owner did swap this Y8 in because the previous had thrown a rod.

This past weekend I did the idle learn process by disconnecting the battery for 5 mins, hooking it up, starting the car and let it idle with no accessories on for 10 mins. Normal idle is perfect @ 800rpm when the A/C is on the idle drops nothing dramatic anymore but is still significant, drops to around 500 rpm or so. When the compressor engages it drops, as soon as the compressor disengages it idles back up. Also I noticed braking has an effect on it as well. So now it becomes a question of vacuum issues or not.

The only thing I still can't figure out is the random miss like feelings. They aren't as prevalent now as they were before, but it still happens randomly, and the weird thing is that the idle isn't affected when it does it, the tachometer doesn't even flinch, but you can hear it in the exhaust and feel it in the car. It's really strange.