Why does a car sound like that when it starts?

[Echonova]

Well the title says it all.

I've been thinking about it for a long time now - nothing in an engine, or the starter should make it make that typical noise when it starts. Hybrids are near silent when they start (even when stationary).

Since it cant be the actual engine (which is entirely silent except for the air noises) - its got to be the starter. Since the starter RPM goes up and down depending on load - maybe thats the repeating noise that sounds like mechanical scratching?

http://www.youtube.com/watch?v=Y2ffO...eature=related

Alot of hybrids also benifit from newer technology. The way I understand it that some (not all) hybrids will stop when the number 4 cylinder (assuming it's a 4-banger) is in the compression stroke. To start moving again when you press the pedal the computer fires the #4 spark plug and opens the injector to only the #1 cylinder adding fuel to compress on it's upward stroke, #1 fires and the engine comes to life like you push started it.

[Atlblkz06]

Alot of hybrids also benifit from newer technology. The way I understand it that some (not all) hybrids will stop when the number 4 cylinder (assuming it's a 4-banger) is in the compression stroke. To start moving again when you press the pedal the computer fires the #4 spark plug and opens the injector to only the #1 cylinder adding fuel to compress on it's upward stroke, #1 fires and the engine comes to life like you push started it.

I've never heard that one before, but it makes sense. I do own a hybrid, I wonder if there is a way I can confirm this. The car is an 09 Camry Hybrid.

When the car is "idling" with the motor off and the battery runs low, the engine will kick in for a minute or two to recharge. There is a very distinct jerk (no starter noise, or any electrical whirring) which confirms your theory. I wonder how its able to stop the crank at a precise location like that though.

[STRteg]

I've never heard that one before, but it makes sense. I do own a hybrid, I wonder if there is a way I can confirm this. The car is an 09 Camry Hybrid.

When the car is "idling" with the motor off and the battery runs low, the engine will kick in for a minute or two to recharge. There is a very distinct jerk (no starter noise, or any electrical whirring) which confirms your theory. I wonder how its able to stop the crank at a precise location like that though.

All done by smart a$$ computers