2008 Prius ICE rocks during Idle/Take-off

Start by replacing the iridium spark plugs using the correct NGK or Denso plugs. Replace the PCV valve. Use a deep socket on the PCV valve, do not use an open end wrench.

Clean the throttle body interior and throttle plate by spraying throttle body cleaner on a cloth, and using the cloth to scrub the dirt off. Clean the mass air flow sensor using MAF cleaner spray.

There is no EGR system.
Then see whether the problem still exists.

 

Good list Patrick, and put some fuel injector cleaner in your tank.

 

The car can feel a bit rough when it's warming up, it shouldn't have any shaking once it's fully warmed up.

 

I think what your exoeriencing is quite normal. You probably have never driven a g2 before.
There’s a big shake when the motor turns on and another when the motor shuts off.

Many many posts here complaining the car jumps or moves when the engine turns on. The car does not move it’s just a big movement of the engine. The reason there’s a big shake is the transmission has to spin the engine to fire it up to be exact electric motor mg1. So you have big engine/trans components engaging simultaneously at the same moment so a lot going on in a blink of an eye.

Normal and very discerning if not used too it.

If the engine was unhappy it would throw a check engine light. Change the oil and install a high quality engine oil like Mobil one 5-30 full synthetic Buy a 5 gallon jug of that at Walmart for $25.

The engine takes exactly 3.5 quarts with a new oil filter. Keep the engine oil at the full line.

 

Don't worry about the transmission going bad yet.

As part of your maintenance activities, drain and replace the transaxle ATF. Buy 4 quarts of Toyota ATF WS. The capacity is 3.9 quarts.

At 100K miles, the engine coolant and inverter/transaxle coolant should have been drained and replaced, although that has nothing to do with the issue you raised. If you do not have a record that this was done, plan to do that as well. Use Toyota Super Long Life Coolant, you will need to buy 3 gallons as you will need ~6.5 quarts for the engine and ~2.5 quarts for the inverter/transaxle. Keep track of the amount of drained fluid, and make sure you add at least that amount back in new fluid. You will know that you have air in the system if you are not able to add the same amount back as drained.