64k mile Cooper S, if I can get it to 100%, it will be the GF's new Mini. She would be grateful!

A little back history, the coop had an oil leak from the turbo line, so I purchased the Detroit Tuned oil line super kit + oil cooler seals + heat shield. I replaced everything and no more oil leak! After this, there was a slight misfire. A couple of cold starts/short runs, and it produced codes P0300, P0302, P0304, and P1497. I swapped the ignition coils with no change to which cylinder had the misfire. I swapped the spark plugs with no change to which cylinder had the misfire. I found a valve cover leak, and I noticed oil deposits on the top of the valve cover, which I've read could be due to a clogged PCV, so I installed a new valve cover, valve cover gaskets, and spark plugs (as preventative maintenance). The good news is the misfire is not as bad now that the valve cover leak and spark plugs were changed! The bad news is, according to Mode 6, it is still misfiring on cylinder 2. It does not have any pending codes yet, but it has only been driven twice for short drives.

According to TSB "SI M11 04 13," this coop does already have the updated timing chain tensioner.

I don't know if the intake valves have ever been walnut blasted. The only way to check this would be to pull the intake manifold correct?

I've heard the high-pressure fuel pump can cause misfiring. I don't like to replace parts unless they have failed, or as needed for preventative maintenance. Is there any way to test the fuel pump?

Any other suggestions on what might be causing this?




Thanks for any help, everyone!!