As said check base idle first, with all electrics off(apart from engine!!) and iscv disconnected I run at around 900rpm, if no joy and it is a instant cut out when off throttle try turning the tps on the shaft so it "sees" more throttle, when the tps wears it causes the carbon track to have a dead spot, the ecu may interpret this as no fuel needed, hence a dead engine, turning the tps will soon see if it is this problem.
tabetha