I have an old Vauxhall Carlton 2.0 automatic that began to stall when stopped at idle or when I was moving with foot off the gas. Handed it into a garage and they replaced the leads, hoses, plugs, rotor arm and distributed cap. The car ran well but it started taking a while to start and I really had to pump the gas. After a couple of weeks the problem returned. Once I got it started it would run fine for a minute but as the revs gradually fell along with gas consumption it eventually stalled. If I put the car into reverse or drive it would misfire as I started to move so I had to use the pedal gradually. The problem gets progressively worse over a few minutes until the car misfires, stalls and won't restart. Broke the timing belt previously and replaced it with no valve damage. Also replaced leaky water pump. Have fitted a new fuel filter and cleaned out the idle control vaalve. Tried disconnecting the auxiliary air valve but that didnt help.
Can you narrow the problem down to fuel, air or electrics from the above information?