BMW Throttle Actuator Repair - WorldwideIf you have a faulty actuator, this has nothing to do with gears.
A common electronics failure with the S85 and S65 engines on BMW's Models: E90 E92 E93 E60 E63 E64 M3 M5 M6
Sadly many people around the world have been mislead by the internet, actuator failure is mainly due to electronic failures and not really much to do with the gears. Generally electronics inside Throttle Actuators fail around 55k miles, the gear wear inside this unit at that mileage would be present on just 3 teeth and you will see some fine dust inside. This is normal, sadly people believe this tiny wear cause intermittent failures. However if you have done 100K+ miles we have seen teeth worn down almost nothing, this causes the gears to bind and lock when closing or gear to slip when opening.