Grinding sound upon startup?

[swich2mac]

From time-to-time, I have noticed that when I push the power button on my Prius, I get this obnoxious grinding/clicking sound for couple of seconds prior to the ICE kicking on. It appears to have a "plastic" sort of sound like maybe from the electric motor. Have any of you all noticed this as well?

[toyolover]

Originally Posted by swich2mac

From time-to-time, I have noticed that when I push the power button on my Prius, I get this obnoxious grinding/clicking sound for couple of seconds prior to the ICE kicking on. It appears to have a "plastic" sort of sound like maybe from the electric motor. Have any of you all noticed this as well?

You may be referring to the sound from the motor/generator(MG). The Prius doesn't use conventional starter. The engine is spinned to a normal running speed in fractions of a second by the MG upon start. You might have heard the sound due to a very cold engine state after parking the car at outdoor overnight. If you have installed the engine block heater like I do, the noise could disappear. If I forgot to plug in it the night before, I could hear the "grinding" noise for about 1/2 - 1 second upon engine start. The noise doesn't seem to be there if I use the BH. Hope that helps.

[swich2mac]

Originally Posted by toyolover

You may be referring to the sound from the motor/generator(MG). The Prius doesn't use conventional starter. The engine is spinned to a normal running speed in fractions of a second by the MG upon start. You might have heard the sound due to a very cold engine state after parking the car at outdoor overnight. If you have installed the engine block heater like I do, the noise could disappear. If I forgot to plug in it the night before, I could hear the "grinding" noise for about 1/2 - 1 second upon engine start. The noise doesn't seem to be there if I use the BH. Hope that helps.

You are correct. It only happens on a very cold day when I first start up the vehicle in the morning. Thank you again for your response.