Southern Alaska has had: (M1.5 or greater) 1  9 earthquakes in the past 24 hours. 2  54 earthquakes in the past 7 days. 3  294 earthquakes in the past 30 days. 4  5,169 earthquakes in the past 365 days.
An engines idle speed is a programmed function. We cannot directly adjust the engine idle speed on a modern vehicle. The power control module or PCM provides all adjustments to the idle speed. Though no external engine idle speed adjustments are possible, many things can and do cause problems.
If the engine speed (for this example) RPM = 6000 revolutions/minute, then the driveshaft speed is the engine speed divided by tranny gear ratio R1 = ( 6000 / R1) revolutions/minute, and the rear axle speed is the driveshaft speed divided by rear-end ratio R2 = ( 6000 / (R1*R2) ) revolutions per minute.