Considering there are a fair few techincally minded types on here, and most MR2 owners don't know what is what with an engine, I though I'd post here and try and get a response.

Basically, my car (MR2 turbo) has the followuing symptoms:

Running rich, mental fuel consumption, intermittent missing on boost, poor running from cold, very high idle when cold and warm.

Does this sound like a vacuum leak?

The early 3S-GTE use an AFM, and as standard have a re-circ dv. Mine has a VTA dump valve - this has always been a bone of contention with MR2 afficianados, as obviously any dumped air is not metered. Could this be the cause of my poor running?

Also seems to accelerate so much better on partial throttle, but at WOT it causes all manner of missing etc.....

Any techincal type thoughts would be appreciated, and don't do the whole "this is a Ford forum" thing. At least I'm asking about cars and not what colour sweater I should knit for my pet hamster....