Trgnmn -- There is a common test to see if the "nut-behind-the-wheel" is functioning at high levels... very simply, allow another different "nut-behind-the-wheel" to go into action in the driver's seat with your vehicle, preferably at a timed autocross or road course event, and compare the times against each other. This common test may have to be repeated a few times to conclude before making further adjustments.