Bad hesitation about a minute after startup - long reach plugs issue?

[RABID_MP5]

I've been getting fairly often where the car almost dies - feels like ignition(?). ALWAYS only 30 seconds to a couple minutes after startup. It will almost die, unresponsive to throttle. Then in about 5 seconds runs fine again, for the rest of the trip. This can either be a stone-cold start or after sitting for only 15 minutes from running. The only thing I did recently is go to NGK long reach plugs - same heat range. I guess I could swap them out again to verify. The coils are recent like a year ago. I did also recently replace the idle air control valve, which seems to behave OK.

 

[RABID_MP5]

I'm thinking the plugs have nothing to do with this. I did pull a P0505 CEL code - idle control system malfunction. Not sure how old it was though. I cleared the code to see if it reappears. Since the IACV just adds air, like opening the throttle, to maintain idle speeds, I don't see how this would cause it. I'm wondering if it is when it tries to go from open to closed loop, and something is screwed up, and after a few seconds goes back to open loop? Maybe like mass airflow or O2?

 

[hornsfan10609]

There is a similar thread to this in the MSP section, my car did it a few times over the summer but it went away.