So my truck is running a bajillion times better since it's purchase from the super nice yet neglectful PO, new o2s, smoked the hood out with some Seafoam, throttle body gasket, plenum, and ditching the reversed muffler, but it still isn't right yet. My CEL is still on but I have a gutted cat so that may be it, I have a new cat and new cat back dual setup on it's way. It's RICH and missed idling after cold startup, idle is a bit spotty, and after every startup no matter temp it's sketchy for a few mins. It runs excellent after reaching operating temp (longer trips) and never did before so I'm happy, but powerwise can't hang with my 305 powered 80's chebby 4x4 :0

So...I cleaned the IAC but I'm wondering if it's shot, could a bad IAC make these conditions happen? It smells (again gutted cat) like when it's running rough it's rich. Thanks!

 

edit - you need to read your codes.... see what its trying to tell you.
edit again. rich smell is too much gas (maybe 02), or not firing hot enough, or leaking injector.

IAC is just a valve that lets air past the closed throttle plates. it important that its operating right, under control of the computer, because the computer has to match the injector flow to the air volume, blah, blah.

about the only thing accomplished by cleaning the IAC is to either unclog the pintle well hole, and/or damage the IAC.

maybe i'm missing it, but i don't see new plugs in your first post. i'd do a tune up with plugs, cap, rotor, maybe wires. after that i'd run a lot of injector cleaner through the gas tank. see if it helps.

 

I did plugs, sorry forgot to mention. Tested the wires as per service manual and all had well within spec low resistance, did not do cap and rotor! Duh on me! I'll do that and post back thanks!