If I leave the car idle the AFR's will go from 14.7 up to 15.9 but every now and then it goes down to 12's and the car will bog a bit while idling then it will go back to normal. The idle is set at 900-1000RPM because of the HKS 280's I have.

Secondly when driving, if I come off the gas fast the car will fall below 700RPM and then goes back to normal.

What is your ignition timing in the idle areas of your ignition tables? (i'm assuming the stock 5 degs).

CJ