Hi, ive got a problem and need some advice please

i got an sti 3, with apexi ecu, running about 330 bhp.

When i put the clutch down and let the revs drop wile coasting to a junction or lights under braking, the rev needle drops quite fast and below the 1000 mark and sometimes stalls the car!!!!!

It dosnt happen when the engine is cold, only when fully warmed up.

Any help or advice will be very helpfull please.............

 

Any ideas please???????????????????

 

not this old chesnut again...... icv/maf/split vacuum pipe/leak between ic and turbo,and finally and most likely spark plugs!