Hi Roland,
Got your CAI kit for my 02 CS 2 months ago.
Car drove fine, then yesterday, funny noise from exhaust, followed by amber engine warning light and change in exhaust note. Reduced engine power. When I restarted the car 3 hours later, engine note and power back to normal, car drives normal, but warning light stays on.
Could the cats had broken up and caused a momentary blockage in the pipes? This has miraculously cleared, hence power back to normal, but the damaged cat is causing the light to stay on. I cant imagine it has anything to do with your CAI, considering the history of events as above.
Any ideas ?