[Sienna.Guy]

I noticed the van rumbles and shakes a little when I turn off the engine while the engine is running.

This is not typical, the engine is usually off when van is in park position, one wouldn’t even notice

It’s easily reproducible: 1) shut down immediately after the ICE is on. Usually first time start up in the morning. 2) Parked, while in EV mode, step on the accelerator pedal to activate the engine, immediately turn off.

Do you feel it?

 

[jareza]

I noticed the van rumbles and shakes a little when I turn off the engine while the engine is running.

This is not typical, the engine is usually off when van is in park position, one wouldn’t even notice

It’s easily reproducible: 1) shut down immediately after the ICE is on. Usually first time start up in the morning. 2) Parked, while in EV mode, step on the accelerator pedal to activate the engine, immediately turn off.

Do you feel it?

I dont have my sienna with me but I was able to reproduce the symptom on my corolla hybrid. Maybe its an atkinson engine quirk?

 

[Sienna.Guy]

Maybe its [the] atkinson engine [shuttering]?

I searched this up and see some results from Tacoma sites. I’m adding this to my list when I make a visit to service.

Could this have been resolved with a better designed motor mount or something else to absorb the vibration?

 

[20swrt]

I noticed the van rumbles and shakes a little when I turn off the engine while the engine is running.

This is not typical, the engine is usually off when van is in park position, one wouldn’t even notice

It’s easily reproducible: 1) shut down immediately after the ICE is on. Usually first time start up in the morning. 2) Parked, while in EV mode, step on the accelerator pedal to activate the engine, immediately turn off.

Do you feel it?

Was the brake light engaged when the jerking happened? I could not replicate this problem of yours.

 

[wscan]

Not sure about the rumble, but there are times when the vehicle will move slightly. I have mostly noticed this when parked with the car on. The engine will start to recharge the traction battery as needed. The engine starts and the computer lets it warm up for 10-15 seconds or so and then starts charging the traction battery. At that point of charging start, a slight movement or jerk of the vehicle is noticed. My parking brake is always set on auto, so it was engaged. If the parking brake were not engaged, I expect that the vehicle movement might be slightly larger, but the movement would still be restricted by the parking pawl in the transmission. This might be what you are experiencing. I think this movement is due to a momentary mismatch between the engine speed and MG1 speed. MG1 speed is controlled by the computer and attempts to match the engine speed to control engine power to the wheels. This mismatch might also happen in the situation that you describe.

 

[Sienna.Guy]

First time it happened was with parking brakes engaged. Then tested and tried with it disengaged, movement is a slight rocking motion.

 

[fotomoto]

Multi-hybrid owner here. This is NOT an unusual event. Unless there are codes, the dealership is simply going to give you a lot of lip service (and possible up charges). My old gen 2 prius was the most pronounced (actually rocked the car back/forth) but it got better with a new OEM HV battery. Each hybrid generation has gotten MUCH better/smoother.

If doing "the driveway shuffle" or other reasons for a quick power up/down on a cold ICE, try using EV mode (when available) to avoid unnecessary ICE start ups. Also turn HVAC off to avoid climate control caused ICE start ups; especially this time of year. And, if possible, let the ICE go thru its warmup cycle before shut down (good advice for any ICE).