Im going to replace the oil in the ol supercharger, it has 210k on it and I don't think it's ever been done ..

Can anyone explain to me how this supercharger works ? I understand how it produces air...
But when does previa tell it to turn on? Should the belt that drives it slip over the pully at idol ?
mine does! Seems like that is not right , I'm getting 24.6 mpg out of this van , so my guess is it's not working , but I can here a valve or something close in the air box when it kicks on ..

it is referred to as the supercharger

thanks for any info on the charger

tj