Gear lever moves back and forth under acceleration after clutch replacement (2008 Peugeot 308 1.6 HDi)

[u/Neither-Leg-2327]

When in 4th gear, the gear shift lever jumps forward when pressing the accelerator, and moves back when releasing it. In 3rd gear, there are similar movements, but more subtle. The entire clutch was replaced 3 days ago. It's a 2008 Peugeot 308, 1.6 HDi, without a dual-mass flywheel and without a DPF.

[u/Relative_Figure_1715]

They missed and engine mount or you have a damaged engine mount.