A Florida man claims his BMW X3 accelerated unintentionally – contrary to his intentions, that is. News story here.
The reasons why are being debated. Could it have been a glitch with the BMW’s “drive by wire” electronically-controlled throttle? Many new cars no longer have a cable that connects the gas pedal to the engine. Instead, sensors translate the degree to which the gas pedal is depressed into how much the engine revs – and how fast you go.
BMW – like Toyota, after similar incidents – claims that run-amok acceleration caused by a defective electronic accelerator pedal is impossible. That it had to be the driver’s inadvertent foot (as when Audi was accused of the same thing – and nearly destroyed by the false accusation – back in the ’80s) or a misaligned floor mat that was the cause of the trouble.
That is being looked into.
But meanwhile, why aren’t people being taught how to deal with problems such as this? It is telling that neither Joseph Cooper – the BMW’s owner – nor the Florida State Police, who were communicating with Cooper via phone in real time as these events unfolded – knew how to slow down and stop a car with a stuck accelerator – whether stuck electronically or otherwise.
There is this thing called the ignition switch, for openers. The same switch that one uses to turn the engine on can also be used to turn the engine off. This will cause the car to slow down.
Cooper’s BMW may not have had a physical key – many late-model cars also use electronics to turn the engine on, too. But there is still an On – and an Off – button. If you push the button for Off, the engine will generally turn Off.
This is the intended purpose of Off.
Of course – for saaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaafety – it is often the case that one must press and continue to press the Off button in order to override the saaaaaaaaaaaaaaaaaafety protocol built into the thing by the manufacturer. Still, the fact remains – the engine will turn off.
Drivers are not told this – and few (apparently) exert the initiative needed to cause the owner’s manual to convey the protocol to them, so that in the event their vehicle accelerates in an unwanted manner, they will know how to put an end to the show.
A second method – in the event the engine cannot be turned off due to some evil electronic genie – is to disconnect the engine from the transmission – and thus, from being able to continue imparting force to the wheels, thereby causing the vehicle to cease accelerating – even if the engine still is.
This is achieved by moving the gear selector into neutral. It works the same whether the car has an automatic or manual transmission. You can also depress the clutch – if the car is equipped with a manual transmission.
This will not blow up the engine – unless the car is extremely old.
Every car built since the late 1980s has computer controls and one of these controls is a rev limiter. It prevents the engine from being over-revved (we used to call this red-lining it) for the express purpose of keeping the engine from over-revving, with the attendant mechanical catastrophe in the event it did.