i had this problem last week..check if the glow plug is glowing hot BUT even if it is that doesnt mean that ur in the clear. sometimes the tiny heat coil in the plug can get pushed inwards. If the tiny heat coil is pushed inwards then u need a new one. If the heat coil is pushed inwards then it wont have enough power to run without the glow starter and thats why the car is stalling when u take out the glow starter.