i have done a search and see alot of post saying it probably carbon build up on the IAC but my problem start after i was on vacation for 3 weeks and the car sat

basically when i went to start it it was very slow to start up but after a few seconds it came back to normal, drove the car around the parking lot, no issues, maybe a little bog when shifting, not much just in the very beginning

next day same thing, this time ran a few errands in the car, everytime after the slow start up when the car was already warmed up if i shut it off and turned it back on it started fine, would leave it parked for a hour or so while at the supermarket came back and it was fine, no jumping rpms or anything like that while driving, then when i would go home, next day same thing, but only the the first start up. no check engine light

so its been three days since i got back from vacation and still does it on the first start up of the day

any thoughts?

 

Fuel pressure issue possibly?

 

I'd check battery connections, and also measure voltage at the battery. Then voltage after a shut down. It could be a slow parasitic voltage draw.

 

i hope not, the fuel pump was just replace by lexus 4-5 months ago

and as far as the battery or drain issue, wouldt that cause a slow turn over? it turns just fine, its after its started the issue

 

From what you've said so far, you really should get the battery and alternator tested. Usually, if it starts up just fine when the car is warm, and only starts slow on a cold start, usually one of the two are the culprit. How old is the battery?

 

What do you mean by slow start up? You press the button, and it takes a long time for it to crank, or does it crank for a long time before the car starts? If it's the latter it is your spark plugs.

 

Sounds like OP is stating the engine slower than normal, thus taking longer to actually run on its own.

Both of the posts ^^^ above ^^^ hold the answer. Weak battery from possibly bad connections or if more than 4 years (3 in hot climates), just replace the battery.