I had a moo valve replaced on my vw caddy ...I believe its on the air intake ,so an easy swop out not being buried in the engine bay .. didn't take them long ....
On a 2.5 it is on the bulkhead in the engine bay behind three other plugs that need to be moved out of the way before trying to remove and replace it. Should take no more than half an hour, bit fiddly but easy to do.