Wheel sensor is definitely the problem. You have no dead reckoning working, the nav is only using GPS signals, and GPS position fixes are not continuous, hence the "hesitation" effect.

Check the speed pulse wiring on the violet nav plug.

The Mk4 only uses one wheel sensor, the older Mk1 and Mk2 used two sensors

The standard Mk4 wiring has the DFAVL – front left wheel speed pulse - on pin 10 of the violet plug. The wire is yellow with a red stripe.

Check this wire is actually fitted to pin 10, and make sure pin 10 is clean and not dirty / corroded etc.

The Mk2 also has DVAVR (front right wheel, yellow/white) on pin 11, but on the Mk4 this signal is ignored.

Maybe you have the speed pulse sitting incorrectly on pin 10?

If you have speed pulse wires on 10 & 11, try swapping them. If p11 is working, and p10 is not, put the working signal on p10.

To summarise:
Violet, p10, yellow/red, DFAVL, Front left, NEEDED
Violet, p11, yellow/white, DFAVR, Front right, NOT USED