Really, check that the air cleaner is clean, Have you looked at the Idle AIR Control valve, and Throttle Position Sensor?

 

replaced the IAC valve, the TPS is fine, K&N filter.
could it be a clogged cat?

 

It is a possibility, it's been there long enough.

 

well before i tear apert the exhaust i found some kind of sensor (possibly air temp?) on the air filter cover that is not connected and a few wires goint to nothing (looks like a temp sensor plug, and another plug with a resistor on it. and a stray wire.)

 

Looks like one the mods being sold on E bay. lol

 

It's probably someone trying to fool the PCM into thinking it's got a dense charge of air. If you've got a scan tool handy, try checking out the Intake Air Temp. If it's just an open circuit, it'll read at -40 degrees, otherwise, the resistor will probably read something completely inacurate. Then try plugging the sensor back in. If this is not the case, just plug the thing in and see if there's an improvement.[/align]

 

i cut the resistor thing off and now it runs like **** when you first start it, so i put it back on and it still runs like **** when you first start it.

 

check the air cleaner, word.

 

air cleaner is a fresh K&N
could it be a leak in the fuel return at the fuel pump?

 

someone told me today the it could be a problem from the factory from when they first came out with TPI.
he said some idling problem due to maybe a valve or the ecu. someone also told me about some valve in the exhaust where the 2 headers collect into 1 pipe. also someone else said it could be the egr valve stuck.