The problem is total advance only works the instant driver come off of throttle, traveling at 3000rpm the advance is reading is 12 degrees at 60% throttle position. The second one takes their foot off of the gas it will spike up to 30 plus degrees for a split second. Very sluggish on take off, no power on take off, idle is perfect at 8 to 12 degrees. The advanced timing makes changes but not at proper times. What sensor controls the computer to know where the issue is or is there another problem to solve?