I replaced/removed the OEM filter+housing over the weekend and installed P'cross filter - relatively straight fwd job. However following a change I noticed that car is a tad hesitant on lower revs which does happen on kick down too, e.g. for those that have driven a diesel it's almost as phenomenon called turbo lag.
I have tested it on several short journeys... interesting feedback + noise but not much gain tbh on 355bhp monster. originally I was after improved feedback at lower revs but was presented with a lag and couple error codes backed up by check engine

Also any hints as to what could have caused P2187+9 error... and what would be a typical culprit/where to start troubleshooting from?
Much appreciated...