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Drive by wire discussion
I just bought a VW passat 1.8T and it is my first vehicle with fancy electrics. One of these being drive by wire.

Thinking about this for a while I was wondering how the ecu handles the throttle.

Can anybody clarify?

My sentiments were that the throttle works the same as a cable but if I was the designer I would......

.....have the throttle body completely closed at zero throttle coasting along and as soon as the brakes are applied I would fully open the throttle body to help with engine braking like a diesel vehicle. As soon as the throttle is actually applied the standard mechanism applies as you can't have a petrol engine run rich or lean.

Being more complex you could even have designed the engine with dual exhaust and dual inlet that can be individually controlled by the ecu. On low throttle or idle only two cylinders would would fire with a clutch engaged balancer shaft to smooth things out, and then, the other two cylinders on the separate throttle body and exhaust would pump air only to cool the turbo.

My funny thinking is, that, with a diesel, you have idle and coasting that pumps 100 degrees and below air through the turbo to cool it down but with a turbo there is no option like that, as it is always at a hot stoichiometric burn.

Is this design somewhere implemented or is it a good/bad idea that is too complex?