Cutting out at certain rpm

[Jackle]

Got up this morning to find the car (325) frozen up, so I gets in and starts it up, was a bit "chuggy" and some of the dash warning lights stayed on (brake fluid level, ABS, alternator) until I gave it a blip on the throttle to 1500rpm.
I set off and find that as soon as I hit 2500rpm it starts cutting out on me, I only had 1.5miles to go so I don't think much of it, thinking its probably a bit of damp got in somewhere. 4 hours later I start up to go home and the same thing happens, warning lights stay on and can't rev over 1500rpm.
An hour later I drive to work, car starts ok, no warning lights staying on, I can rev past 2500rpm now, but only as far as 3500rpm when it starts cutting out again. It's still cutting out at 3500rpm when I came home from work an hour ago.

I'm a little stumped here guys, it only cuts out when I get to a specific rpm, before that it runs smooth as normal. Throttle position has no effect on when I cuts out, its only when I get to that specific rpm.

Now I've asked on here it'll probably be fine in the morning...

[ian332isport]

Possibly the Air Flow Meter (AFM).

I'd make sure the flap is nice and free to move, and does not have any tight spots.

Ian.