Hello all. I am a newbie to Mini's. I recently bought a 03 mini base. I had an oxygen sensor fault and the guy I bought it from had new oxygen sensors. I installed both and cleared/reset adaptives. I drove it for about a month and started getting lean codes on bank one. changed fuel filter and reset some adaptives and have not had that code back but I am getting intermittant misfire cylinder 1. Tried new coils, plugs, wires, swapped injectors. sems to always run kind of rough at idle. Does the 2003 engine have the valve carbon issue? Does anyone have any other ideas? I can go weeks without a light on or sometimes it comes on within a day. Thank you

 

Lean condition could be vacuum leak. Try a smoke test. I have a link to a good smoker if you would like it let me know.

also could do a compression test and leak-down test