Throttle Lag On DBW

[cali yaris]

If that were true the engine would stop running. The engine has to have fuel to idle.

Actually, you're right. But in DFCO, the engine isn't "running" or idling, it's just spinning. There is no spark and no fuel during DFCO.

Tamago, the "D" stands for deceleration, so it's clear that's when it happens.

[Zaphod]

It's just compression braking with no fuel, as the drive train is turning the engine and pumping air through it.

What gear you're in determines the RPMs that your engine is running at, which determines how much air is being pumped through the engine, which is the resistance that slows the car down.

It's pretty easy to get used to judging distance and timing compression braking pretty much the same as you would with your friction brakes to the point that you use a lot less friction to slow down (and less gas with DFCO).

Honestly, I've noticed the lag with drive by wire more starting out in first on a hill. The workaround for me was to give it more acceleration earlier than I normally would with a manual transmission.

[Tamago]

Originally Posted by cali yaris

Tamago, the "D" stands for deceleration, so it's clear that's when it happens.

and how does this work on an automatic? sounds highly inefficient as the engine revs will drop off, torque converter goes jellylike and now you have to build all of that energy back up to get the car moving again. i guess on a super long decel it would save fuel but otherwise not really ?