Hi,
Au2 fairmont 2000 model after market dual fuel, runs fine on petrol. When running on gas and driving along, i release the accelerator to slow down, the car drops below idle speed and can stall, or it seems to recover back to idle speed. More likely to do it in warm weather. Doesn't do it when stationary in the driveway, only when driving. Any clues most gratefully received.
Andrew

Check the balance line from the convertor to the air filter box, it may have fallen off the bottom of the convertor or it has a small hole in it. Even a small hole in it will cause the engine to stall on deceleration on gas.

Thanks Rod, you were right, the balance line had come out of air filter box. Much appreciated.