Manual tranny, why didn't you say so? :-) Yeah, I guess you would notice the difference.
But I think you've hit on the difference, as I vastly simplified what is going on. Not that I expected you to read the link I gave, but it does give some explanation as to what's going on. And what's going is that the pistons are still going up and down because air is continually drawn into the engine. Air is compressed, and even though there is no fuel to make it go bang, that air still needs to uncompress and so returns a lot of the energy back to the crankshaft. Ergo, very little engine braking.
As a personal example, our diesel Sprinter van (automatic tranny, FWIW) had some degree of engine braking, but so little that I wouldn't rely on it for much more than coasting to a stoplight or other low-stakes slowing. If I'd like to stop sometime in the next day or two, I hit the brake pedal.
But I think you've hit on the difference, as I vastly simplified what is going on. Not that I expected you to read the link I gave, but it does give some explanation as to what's going on. And what's going is that the pistons are still going up and down because air is continually drawn into the engine. Air is compressed, and even though there is no fuel to make it go bang, that air still needs to uncompress and so returns a lot of the energy back to the crankshaft. Ergo, very little engine braking.
As a personal example, our diesel Sprinter van (automatic tranny, FWIW) had some degree of engine braking, but so little that I wouldn't rely on it for much more than coasting to a stoplight or other low-stakes slowing. If I'd like to stop sometime in the next day or two, I hit the brake pedal.