Has anyone experienced their car's tachometer suddenly jumping above 3000 RPM and then dropping back down while driving?

Does anyone know why the Yashenti dashboard needles suddenly drop to zero while driving and then return to normal after 1-2 seconds? Thanks, everyone.

Is there any other Coaster owner experiencing the same issue where the engine RPM fluctuates up and down while coasting in neutral?

Is anyone familiar with solving the issue of idle speed occasionally rising to 2000 RPM and then dropping back down on a stock MG HS? It's particularly noticeable at low speeds.

When driving a manual transmission car, if you hear a rubbing noise from the engine slightly above 2000 RPM, but it disappears above 2300 RPM, what could be the reason?

Has anyone experienced this: when driving normally and approaching a traffic light, you brake and almost come to a stop but not completely, and at around 10 mph the RPM fluctuates while the gear has already dropped to second gear?

Has anyone experienced their car's tachometer suddenly jumping above 3000 RPM and then dropping back down while driving?

Has anyone experienced their head-up display flickering while driving?

When I start the car, the idle speed is around 2000 RPM, but after a while, it drops to 1500 RPM. It takes quite a long time to go down to around 1000 RPM. Does anyone know what's going on?

Has anyone experienced the issue where the RPM doesn't drop after releasing the throttle on a Cayenne? Looking for solutions. 🙏

Help, everyone! Has anyone experienced this? While driving, the dashboard suddenly shows "brake," and the car brakes automatically, even though there's nothing in front.