Toyota Repair: idle control valve, toyota avalon, life span

Question
any idea what's the life span of this part ? I have a 1999 toyota avalon XL, having to replace this part. what's the cause of this part going bad ?

Thank you,

Irit

Answer
The cause for the valve to stick is carbon and gum deposits in the throttle body and the valve, this is mostly caused by blowby fumes from the engine being redirected into the intake system for emission control reasons. There's really no way to predict how long one will last but it should be between 60-120K miles, maybe more.