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Bad to run the car for a short duration, turn it off, and start up again? - Motor Vehicle Maintenance & Repair Stack Exchange

But if Prius'es do that and many of the first generation ones' engines are still in good shape, what exactly did Toyota do right that other manufacturers may be doing wrong? My father-in-law has the MB ML400 and the ICE too stops when the vehicle is not in motion. The turning on of the ICE in the RAV4 Hybrid doesn't feel as intrusive in terms of vibration/shakiness though.

It's as if we have a choice when unlike BMW or MB, we can't turn the feature off.

 

[rdgrimes]

Its not bad for it at all.
The ICE runs enough to keep warm, so there's no cold starting. When it does start, the MG spins it up to 1000 RPM before any spark or fuel is applied so its well lubricated.

 

[jrohland]

My 2005 Prius used a thermos bottle and pump to keep hot coolant hot while the ICE was off. Normally it wouldn't use that unless the car was shutdown. However, it could use it if you had an extended period while the ICE was off.

As rdgrimes said, using the large generator as the starter, gives a number of advantages over a traditional starter motor.

ICEs only really wear out while running. The less it runs, the longer it lasts. This is why hybrids can go much longer between oil and filter changes.