ok i dont know what would cause this.....if its really cold out like 30 degrees...when i first start my car u can hear a miss in it untill about 5 minutes of warming up it goes away...if its warm out say like 50 and up its doesnt do that on cold starts.....i have brand new plugs, wires, accel coil, new module, cap and rotor, fuel filter...it runs like a dream it just has a miss on collld days on cold starts if i put it in gear tho it doesnt miss... just in park or neutrel for the first 5 minutes of start up........my manager said he thinks my computer is messed up....you guys think my jet chip causes that...only reason i have it is to cut out my speed limit cuz i have gears and havent corrected the speedo

 

It might be worth a try to put the stock chip back in and see if the symptoms are the same, just to rule that out. I wouldn't be surprised if the Jet chip is the problem, since those companies usually just tweak the fuel and spark curves, so it may be making the engine run more lean or rich on cold mornings than it wants to. Just a thought. If the cars runs fine except for the missing on start-up on cold days, than you can pretty much rule out the computer, too. Generally, when a computer goes bad, you will know it.

Have you checked fuel pressure recently?