Cold starts weird.. video inside

[Frey7190]

So this happens to my explorer when its cold and hasn't been driven for 24hours or so.. As you can see in the first vid, it turns over nicely but for a sec stays at around .5rpm and has a slight sputter, then kicks back to normal idle. The second video shows how it usually starts up, and doesn't have that second or so delay.. Car overall drives fine, I just was wondering why it does this at cold starts.

Cold Start:
http://s274.photobucket.com/albums/jj243/freysa4/?action=view&current=CIMG7447.flv

How it usually starts up:

http://s274.photobucket.com/albums/jj243/freysa4/?action=view&current=CIMG7448.flv

-- ALSO for your guys' fyi, the fuel injectors were replaced about 4k ago, and thats when I started to notice it does this.. I didn't replace the injectors, a shop that lost my business (for other reasons than this) did the repair.

 

[eXcali]

I watched each video several times and didn't really see much of a difference. I'd be more concerned about the sound of the engine when it's starting, each time it sounded the same. The cold start showed the needle lagging for a second but from what I could hear there was no difference in the idle speeds.

Cold starts are naturally more stressing on your engine so this could explain any vibration or stutters your seeing on the initial cold start. Things you can do to combat this a little is do a flush on your next oil change to help clear out any sludge that will slow oil getting thru the motor on a cold start and run the recommended oil weight for your vehicle. I hope this advice makes sense as I'm almost falling asleep.