Right, so I did my first track day as S/C on sunday at rockingham, had a couple other issues show their head, but they are known and easily solvable. This one however isn't... not in my head anyway.

Since sunday, the engine won't idle as it usually did. It normally warmed up and settling to about 800-900ish. Now it just sits dead on 1k pretty much whether it's hot or cold.

Not only that, but when I stop and let it idle, it will vary between 1000 and 1250 rpm, seems completely random.

Now normally on cold start ups, it used to sometimes stutter a bit when on half throttle between 2 and 3k rpm as if it was just on the verge of boosting but not quite, it went away when it was hot. But now, it doesn't do it at all, but in its place, there is the usual supercharger whine, at 1000rpm..... :/ I'm pretty sure that's not normal, and it does it a LOT more in 4th or 5th gear, say I'm cruising in traffic and I slowly pull away in 5th, the whine picks up instantly, louder the more throttle I use, it starts higher pitched then lowers and goes away at about 3k, then you can start to hear the usual familiar whine coming in.

I've checked the servo hose, and it was fine, and the fuel pressure regulator was as well. Changed the actuator/solenoid for a brand new one I had lying around, and removed fusse 8 of the ECU for 5 minutes, none of it made any difference at all. It still starts up and idles all over the place.

Has anyone got any idea, as this is my daily car and whatever it is I'd rather fix, that it leave me stranded at the side of the road with a larger repair bill.

Thanks

Seb