Car Start Up

secondly, as the software is not expecting you to do this it can 'upset' the system. I remember one model where it would bring the engine-management light on, the system detected that the throttle was not in the idle position during cranking, and reported a fault for the throttle position sensor, that was listed as being caused by an over-tight throttle cable.

Thirdly, if the car has a turbo it will cause the turbo to spin up to a far higher Rpm just after startup, before the oil is fully circulating, thus shortening the life of the turbo. The same is true of the engine.

Finally, on some cars pressing the throttle to the floor during cranking cuts the fuel off completely, as it is interpreted as the driver trying to clear a flooded engine.

It is a habit some drivers learned back in the days of carbs and manual chokes, before turbo chargers were common, where it could help to start a car that was reluctant to start.