What did I hit?

Yes, it does seem more startling in reverse, even after 13 months in my case. It's normal behaviour, though.

 

actually, i've nevr noticed that. did it just start, or was it there on your test drive?

 

My 2009 Gen II does that occasionally, especially when the ICE is cold. I've always supposed it's just the same behaviour I've noticed with other (non-hybrids) when the engine is still cold (i.e. not too much to agonize over!) If you're really worried, you might try cleaning the sparking plugs! (Is the system throwing up any codes?) - hope this helps - Wil

Edit: Engine mount? …er that's it!

 

maybe drive a new one to see if it does it.

 

Hard to evaluate just by the definition "klunk".
But I'd say my Prius never or has very rarely "klunked" when the engine starts.

I'd say if it's loud enough and shocking enough for you to routinely notice it? Then something is wrong.

 

Even weirder I swear it happens to me in virtually the same place every time.

 

Yes my 2010 was occasionally clunky too. I chalked it up to a software hiccup and mistiming the spark or fuel injection during startup. My CMax doesn't do this.

 

I never notice anything, and I'm pretty cognisant to engine sounds. Maybe a loose engine mount?

 

I don't know how anyone cannot notice the ICE starting up while backing up. When cold, my ICE generally starts right about when I get halfway out of the garage. It's never made me think I hit something though, but it's definitely not something I don't notice. I guess I should note that at that point the SiriusXM radio is just about to find it's signal and kick in, so the car is quiet when the ICE kicks in. Perhaps those whose radio is already on just don't notice the ICE kicking in as much?

 

You've already said it. We all notice it but have gotten used to it so that it is hardly noticeable. I have a PiP so I rarely hear the clunk as the ICE usually engages while I am in motion and I don't notice with the wind and road noise. However, when I run out of battery, yes, I do notice it.

As to how long to get used to it? I don't know as I haven't gotten used to it yet. I was backing up the other day with no battery and the engine clunked to life startling me after 3 years and 83k miles of ownership. But like I said, I have a PiP so this was a rare occurrence.