dies at idle

Hi

This is my first posting here in the hope that someone can help me identify a problem. I have a 93 3.9EFI auto with LPG conversion. On occasion, not all the time but increasingly so, when approaching any kind of obstacle that requires the revs to drop to idle, the engine nearly, and often does die. Starting it again seems to be no problem and when driving it there are no apparent problems. The following bits are new - plugs, rotor, leads. I can't say whether it happens when on petrol as well as gas as we are on gas 95% of the time. I was wondering if this was symptomatic of the air mass meter. The only solution I have at the moment is to adjust the idle screw to allow more air in - crude I know - but necessary for now.

Any ideas greatly appreciated.

Thanks

Mark

Check all your vacuum pipes around the engine bay first,could be your air flow meter - they fail frequently as a result of backfire from LPG sytems.It does sound like oxygen sensor failure to me tho.