Toyota Carina stuttering/cutting out

Hello,
I've had my Carina E Auto for 2 yrs - great car but recently I'm having major problems ...
As VERY low revs she stutters and has cut out on me - I've had her in the garage twice in 6 months - they cleaned out the throttle body and the sensor but 2nd time round it didn't work :(
Only way I can describe it: if driving a manual and you get the an almost full stop but forget to dip the clutch the car stutters - it like that - if I keep the revs up she's ok, if I use neutral at junctions/lights she's ok, and I've started using '1' for parking etc with no problem...
She drives well apart from this - although she's 22 yr old I've only got 68,000 on the clock - she was garaged and well looked after prior to me buying her and the only problem I had last year was the radiator had to be replaced.
IF anyone has ANY ideas I would be very grateful as I can't find out if its a possible oil change - if the gearbox is going or just the sensor
Cheers