It started slowly about 1 month into ownership (about 6000 miles). 5 months into ownership, rattles became common and steady.
I compiled them in this video. Dealer could not replicate (they tried once when I left car overnight). About once per week I get a normal non-rattle start. I check my oil level once every few days and it's always at the top mark, so it's not a lack of lubrication problem.

Part I:

Part II:

Other manufacturer's rattle/knock issues:

Toyota Rav4:
TSB-0041-13 - Gear Assembly - Camshaft Timing

(Corolla) TSB - Brief Engine Knock/Rattle Noise at Cold Startup
T-SB-0087-09 - March 13, 2009

TSB - Engine Knock/Rattle/Squeak on Cold Start - Toyota Nation Forum : Toyota Car and Truck Forums

 

I recall someone saying that it may be a stuck starter.

 

I also recall someone saying that they experienced some chatter during starts. Maybe mine is a rare problem.

 

Mine does almost the exact same thing. Mine is a little more squeaky though, and it sounds to me like the belt or something.

 

My fit does this at temps below 10 deg. f. It does it about 20% of the time. It's the same noise. Dealer couldn't get it to do it, and then the weather turned warm. I had the dealer listen to the noise I had (like you) recorded. They agreed it was not normal, but if a dealer cannot reproduce a noise, they cannot get the okay from Honda to try to diagnose it. The best guess I ran across here on the forums was that it is the timing belt tensioner device. The oil pressure is part of this tensioner system, I think--hence the temperature sensitivity. Honda corporate told my dealer to tell me to use genuine Honda oil filters. I was using a Wix filter. So now I use Honda filters and Mobile 1 0w20 synthetic. This coming winter if the noise starts to happen again, the dealer will not have "non-Honda filter" to offer as an explanation. My guess is that this is going to be a very difficulty problem to diagnose and have fixed under warranty. Good luck to you and all who have experienced this noise.

 

yea I am noticing it too.. the rattle goes away once the car is warmed up.. only that first ignition, I hear a rattle..

 

I've been getting this a lot lately with my '15 Fit. Anyone had anything done about it at the dealer?

 

Update for November 2015 @23,000 miles:

The rattle comes on about 90% of the time when cold starting the engine. It does not matter if it's warm or cold outside. I switched to a higher end Fram oil filter and Quaker State synthetic and there's no difference whatsoever from the stock Honda motor oil and stock oil filter.

This seems to be one of those issues that will be hard to diagnose. Also, I am starting to notice engine hesitation at low 2000's rpms in 2nd gear and medium acceleration. Another poster in this forum noticed the same thing. It does not happen all the time, but it seems that it's getting worse.

So, the rattle is very consistent, but I am starting to see the long term negative effects on the motor during normal operation. From the looks of it, my motor will probably be ok for the next 30,000 miles. Who knows.

I decided to not bother with the dealer anymore, and just live with it. I am switching to dealer oil service until my basic warranty runs out. Since the dealer could not diagnose the problem (this is documented in their invoice), then if the motor undergoes major failure ... well ... warranty. I've done my due diligence.

Other manufacturers have similar issues:

Rav4 rattle:

Corolla rattle:

(Corolla) TSB - Brief Engine Knock/Rattle Noise at Cold Startup
T-SB-0087-09 - March 13, 2009

TSB - Engine Knock/Rattle/Squeak on Cold Start - Toyota Nation Forum : Toyota Car and Truck Forums

 

I don't think the cold start rattle is related at all to the hesitation in the low 2k's of 2nd gear. I was the first one to write about the 2nd gear stumble that I've had since day 1 of owning my car, and I have not yet heard any type of rattle when starting, even on sub 20-degree nights.

Also, my hesitation has not gotten worse at all. It's the same. I rev 1st gear a little higher and shift into 2nd gear above 2k. I think this remedy has worked for most people that experience this.

Great videos though! I think those will be helpful to anybody that is trying to have this rattle diagnosed and getting a runaround from the dealer.