Jolly Green Giant

Hi guys wonder if anyone has any ideas?

I have a Subaru Impreza Turbo 2000 AWD on a 2000 plate.

I have had this for over a year and regularly get it serviced etc but recently I have noticed when slowing down / stopping and I dip the clutch it the engine nearly stalls? when the engine is idling the RPM counter wavers between 800rpm / 1000rpm, but when accelerating / normal driving there are no problems, any ideas what the problem could be and what I could do to resolve this?

If any use I always use premium grade fuel but not sure what the owner used prior to this?

I have been told it could be a dirty injector and was advised also it could have been a "burnt valve" I had a compression test and a leakage test but all results came back satisfactory.

Eprom

My bet would be the MAF sensor; I have a MY99 and have changed mine twice now, about £70.00 from dealer 15mins to fit. A word of warning though, sometimes this does not show up a fault code on the select monitor, try and drive off boost until it is sorted, it can cause the fuel mixture to run lean on full boost, which can cause DET.
Hope this helps

Jolly Green Giant

Thank you Eprom for your help