We have a 2009 Clubman S with about 100,000 miles. I pulled the engine to change the clutch, timing gear, and walnut blast the intake valves. I reinstalled the engine and took it for a test drive and it seemed to run fine but had an oil leak at what turned out to be the oil feed for the turbo. After I fixed that, the car again ran fine on a test drive.

However, now it will start but not run. I pulled codes and found a 002BC which suggested a MAF or a throttle body. Since both were original, I replaced them and smoke-tested the intake. All was well, and I started the car and it ran for about 10 minutes idling in the garage and then stalled. It now will once again start but won’t stay running, and there are no fault codes..

I’m confused why this would run for 10’ after sitting overnight, but won’t restart after stalling. Could this be a fuel issue? I replaced the HPFP a year ago, but the in-tank pump is original.