Originally Posted by AlanAZ
What's the process for cleaning them?
So what the VANOS solenoid is is a short, thick, metal tune with holes in it and an inner rotary valve that moves to allow different combinations oil passages to open up. I guess they just get clogged up over time. Considering the solenoid part is an electronic component I just used CBC brand electronic parts cleaner and then shot some shop air at 90 PSI into all the orifices to clean everything up and dry them out.
Both exhaust and intake VANOS solenoids are the same part number. Swapping locations of the solenoids from intake to exhaust sides when re installing them lets them run different oil control profiles; because now one is controlling the exhaust cam rather than at its original location for controlling the intake cam and vice versa. In my thinking, swapping them keeps them from "running in" into just one set of the oil control routines and they get to act like new parts.