If it's an EFI vehicle the engine may start and then cut out. If the vehicle is on an angle it might not even start at all!

CHECK

If the vehicle is on low but the light hasn't come on yet (don't rely upon those lights as sometimes they don't come on), check the angle of the car. A vehicle on a flat level should be okay, provided the pick up pipe in the tank is correctly fitted. If the pick up pipe is slightly higher in your vehicle, then being low on petrol may cause the engine to start and then cut out or operate erratically. It is not good to run low on petrol in any vehicle as it can cause damage to the fuel pump, the fuel filter and also the injectors and/or the carburettor depending on whether it's a carburettor or EFI vehicle.