I3s jerking/jumping setting off

mdean22 · Dec 3, 2024

My wifes i3s has just done 50k miles it si a 2019 car. When setting off it clunks into drive then is fine. It kind of feels like ther is play is the drive system. I would kind of describe it as a prop shaft on a modern car having play in the bearings. Is this a known fault if so any guides on places to look.

Thank you in advance.

mojo · Dec 3, 2024

I guess it could be one of several things, but the first thing I would check is that the brakes are operating exactly as expected, and not binding/dragging. Compared to motor mounts, drive shafts, gear bearings, etc., it's an easy thing to check (and to fix if that's where the problem is).

mdean22 · Dec 4, 2024

It's definitely not the brakes. The car will be in neutral foot off the brakes when apply power it jumps into drive. You can be driving along take foot off accelerator then back on it will jump every time power is applied

alohart · Dec 4, 2024

mdean22 said:
It's definitely not the brakes. The car will be in neutral foot off the brakes when apply power it jumps into drive. You can be driving along take foot off accelerator then back on it will jump every time power is applied

If your motor mounts are worn out, the motor might be flopping back and forth when decelerating then accelerating or when starting from a stop. If this is happening, the motor mounts need to be replaced ASAP before other damage occurs.

mdean22 · Dec 4, 2024

alohart said:
If your motor mounts are worn out, the motor might be flopping back and forth when decelerating then accelerating or when starting from a stop. If this is happening, the motor mounts need to be replaced ASAP before other damage occurs.

Ok cool how do I check the motor mounts is this a topic that's been covered before?

alohart · Dec 5, 2024

Their sides can be seen inside the rear fender wells on the panel between the fender well and motor compartment. If these are moist, the fluid inside is leaking which means the mounts need replacing.

TedStriker · Dec 7, 2024

I get this to a small degree. Mine's a 2018 REx on 106k miles so would have the newer mounts. It's not bad but definitely a clunk sometimes going from N to D. Also sense it when pulling away after coming to a stop using regen braking. It's not bad enough that I've thought of doing anything about it but it's definitely there.