I hear a lot about 'having the vanos serviced/ refreshed' on the M54 engine.
Four questions:
What is the VANOS? What does it do (I can't be bothered to Google it)!
At what mileage/ age is the consensus to have it serviced?
Are there any telltale signs it needs doing?
Is it a simple job to do whatever it is that needs doing to it?
I am just about to take delivery of a 2001, 54k miles Z3 with an M54. I want to get any preventative stuff done before I start ripping the car to bits!
Four questions:
What is the VANOS? What does it do (I can't be bothered to Google it)!
At what mileage/ age is the consensus to have it serviced?
Are there any telltale signs it needs doing?
Is it a simple job to do whatever it is that needs doing to it?
I am just about to take delivery of a 2001, 54k miles Z3 with an M54. I want to get any preventative stuff done before I start ripping the car to bits!

