The Genie Between You and Acceleration

When we were kids, we were told to wish for things. Imagine it, pray for it – and it might be so. At the genie’s whim, of course.

New cars work a lot like that. You have very little physical control over its workings.

Instead you have wireless control.

Which really means: The computer controls the workings of your car.

For example, “drive by wire,” which almost all new cars have and most cars made during the past five years or so, too. Instead of a physical cable connecting the gas pedal to the throttle, it’s all done electronically – by wire.

Actually, by sensors. $50 Gift Ca... Buy New $50.00 (as of 03:30 EDT - Details)

You push down on the gas pedal and the system uses these sensors to register the depression of the pedal and the computer signals the throttle to open to the appropriate degree.

This is done for several reasons, among them packaging. During the car’s assembly, it is easier to just plug things in rather than have to manually install and adjust a cable. No need to feed a cable through the firewall, then hook one end to a throttle arm and the other end to the gas pedal.

It also eliminates production variances; the possibility of one car’s accelerator pedal feel having slightly different feel than another identical car – same year/model/make – because the throttle tension of car “a” was adjusted a bit looser or a bit tighter than the cable of car “b” right behind it on the assembly line.

The car manufacturers operate on the same principle as McDonald’s. A Bic Mac ought to taste exactly the same, whether you’re eating one at a restaurant in New York – or LA.

The downside – when it comes to drive by wire – is you’ve just made a simple thing very complex – and also something that can’t easily be fixed by the side of the road (unlike a snapped throttle cable).

Also, the drivetrain is now much less under your control. The computer decides how much throttle will be allowed and can (and does) back off or even shut off the throttle, for various reasons, none of which you get any say in. $25 Gift Ca... Buy New $25.00 (as of 11:10 EDT - Details)

Or the other thing (wait).

It also takes time – perhaps only fractions of a second – for the computer to interpret data and then trigger a response to it. This is why some new cars are afflicted by a kind of turbo lag, except it’s not caused by the turbo. You floor the gas and – for a noticeable fraction of a moment – nothing happens. It is during this fraction of a moment that the computer is deciding how much to open the throttle and then commanding it to do so.

A physical throttle cable delivers instant response (assuming no actual turbo lag). You are in full control of how much the throttle opens – and when.

Problems are also easy to identify – and cheap to fix. The cable is either connected and tensioned correctly or not. You can see (and feel) it. If you need to replace it, all you need is a cable – and even stealerships can only charge so much for a cable.

Or, make one. Rig one. See earlier point about by-the-side-of-the-road repairs. Very doable with a cable.

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