I've bought a 2005 R53 Mini Cooper S from Copart with the description stating it had an undiagnosed noise from the engine bay. After getting the car, I quickly discovered a very strange noise on lift off and a lack of power.
After a bit of research, its pointing towards the timing being out, so I previously changed the timing chain, serviced the supercharger, replaced various gaskets that were leaking, removed the catalytic converter internals as it was blocked, replaced the fuel pressure regulator vacuum pipe, tested the injectors and replaced the fuel filter. It is now running so much better than it did when I got the car!
On all my previous videos, I was always getting comments about checking the bypass valve, which I did when I serviced the supercharger and thought it was ok. I then came across Rooster Racing on Facebook that offer a remanufactured bypass valve with an uprated spring for £83 delivered and they will refund £20 if you return your old unit. So for £63 I thought I might as well change it to make sure it is working perfectly. Follow the steps I take in replacing the bypass valve in this video. Plus I quickly fit a brand new 2nd hand cat.
Rooster Racing:
/ brownpantsminiparts