Posting here as the tech forum is very quiet...
I have a uk '03, 115k, generally in good mechanical shape. I changed the clutch last weekend at a friends place and due to rot on the exhaust I fitted a Scorpion Y pipe and some generic sports cats while doing so.
Test driving afterwards I was slowly adding load and came to a point where I was stretching it out. In third and fourth at 4500 rpm at high throttle angles I hit a rev limiter. A harsh sudden and complete power cut, not the slurring power reduction of an ASC event.
It was concerning as it put huge driveline shunt into a brand new clutch. However it seems to be ok...
I came back, shut down, restarted revved in neutral and it span to beyond 4500 happily. So, I drove home later and the problem had gone. I'm yet to see it happening again, but I commute in other cars or on foot, I'm hoping to test today.
So far I've checked the intake and exhaust for leaks and nothing found. No stored DTCs in the ecu either. I'm thinking of taking it in to see if there's any stored abs system faults, but might be a few days before I can.
My suspicion is an electrical fault, anything on the air management side capable of causing a hard stop on the rpm at 4500 would manifest in other ways too, and currently it starts and idles fine.
I found some old posts mentioning vaguely similar situations, but no solid conclusions.
Has anyone seen this before? Or any thoughts on what might be happening?