#5043, "RE: Megasquirt 2 idle issue 3k" In response to In response to 2
Vacuum can be off by so many factors. Leaks, RPM, Timing, AFR, cam overlap.
The first thing you need to straighten out is the 3000 Idle. Once you get that under control you set your timing where it should be. Then you go after setting your Idle mixture based on vacuum.