I own an 04 S2000 AP2 with 55k miles and I've been having this small startup issue ever since i bought it a couples months ago.

Location: Northeastern USA (hot humid summers/cold freezing winters)

The first start of the day/a few hours always fails on the first try. Then the second try the car sometimes turns on almost perfectly.
Either that happens or the first try takes extremely long and sounds like its struggling to get into get into idle rpms for 2 seconds then runs normally.

Is this a common problem? Is there something i can do or check to fix it?

Ive already changed the spark plugs to NGK Iridiums.

I have the same problem as this guy.

http://www.youtube.com/watch?v=VEezI4XKB5w

 

So slow cranking?

 

Exactly

 

Check voltage at battery

 

If memory is correct, car will start with 12-13 but a new battery is around 14

 

Have the same thing, stumbles a bit on first start up now the temps have dropped. From what I gather, the ECU is a learning unit in that it will self adjust to the temperatures. A few more cold starts and it should sort itself out...

 

Pretty much this.
I have the same thing as well, and my starter sticks too.

If you're really worried about it, you could give the car a little bit of gas as it's trying to start. However, like Arsenal said, the car has a learning ECU, so it's best to just leave the car and let it try and start. It will evntually sort itself out. It's just a quirk of the car I believe.

When you're starting the car cold, just make sure you're giving the fuel pump enough time to prime (you can hear it priming once you turn the key, and I usually wait until the seatbelt warning has beeped all six or however many times before I start my car). I find that if you cycle the key an extra time or two for the pump to prime some more that it starts a little easier the first time.

 

Hold you starter button for a split second less. I'm in Alaska and have sorta the same issues. I perfected starting my car cold without any issues drunk post-****

 

i live in eastern canada and mine does the same thing in the fall when it cools down.

 

http://www.youtube.com/watch?v=VEezI4XKB5w

Here's a video of someone who has the exact same problem I found on youtube. I'll put it on the original post too.