There is no combustion going on when e.g. you release the accelerator coasting towards a red traffic light and the engine is pushed by the momentum of the car above the 1500 rpm mark.

Also when descending a hill and you keep the car into gear the vaccum valves shuts the fuel of --> no combustion.

This is the story for all K-Jet engines you find in W 123, W 126 R 107 and alike after MJ 82 (or so)

The feature of the power laps during shifts of automatic transmissions only applys to cars with networked computer control of engine and gear box like in new Lexus, new Mercedes and alike.

The W 123 and W 126 (and early 124 with four speed auto) is vaccuum operated and has no influence on fuel supply.

Kind regards
Eberhard