2002. 150k miles. 6 cylinder.

my engine has been struggling at late when i pull up to red lights, waiting in traffic etc... but usually only when i first turn on the truck. generally i could feel it about to stall so Id put it in park and give it a little gas until I had room to go. recently got a fuel injection service thinking that may fix it. but it didnt. and now I generally cant feel the engine about to stall before it does.

my air filter looked dirty so i changed it. new fuel filter. Could it be the IAC?

 

Couldnt hurt to clean the IAC,but I would think that if THAT were the case it would be doing its "thing" all the time.You might want to clean the throttle body as well.Ive seen ports get clogged up(partially) and cause issues.