Rep Power: 0

Turned the key when your car was already on . I did that earlier tonight...didn't even realise my car was already on (damn quiet Honda motors). I know this isn't good for the car, but what exactly does that damage, the flywheel? I hope I didn't damage anything, I didn't hold it for long, but still, metal grinding metal is never good.

 
Rep Power: 338

that would be the starter. If you do it a lot, or too long, you'll burn the starter. Which in turn, will destroy it.