My 2000 5.3L Chevy C-1500 won't idle.?

I have replaced the MAF, IAC, MAP, PCV, air filter, spark plugs and spark plug wires. About 4 months ago the fuel pump and fuel filter were replaced. It will idle roughly when still cold but it will not idle at all after it starts to warm up. It runs reasonably good at highway speed. This truck has 150,000 miles on it.

My 2000 5.3L Chevy C-1500 won't idle.?
Have a trained ASE tech check out your vehicle, there are alot of things that can give you that problem, a bad fuel regulator, stuck open EGR, vacuum leak from an intake gasket, fuel injector leak, etc. Pay a diagnosistic fee and have it done right. All Autozone will do is pull a code and sell you a part. Its a free check because they are in the part selling business. If it doesnt fix you problem, they dont care, you didnt pay for a diagnositic, it was just a free check. Good luck
Reply:First off you should be getting a service engine light. If not the light may be burnt. Autozone scans for free. Bring it by have them scan it and see. My question would be though after you changed all these parts did you disconnect the battery for about 10 mins so the computer can reset? You have to do this or it will still show fault even though you changed the part.
Reply:look for vacuum leak at the intake manifold. it is the most common area on 5.3L engine
Reply:replace cold sensor valve and idle valve
Reply:Probably just a clogged EGR valve.
Reply:did you check the throttle position sensor.thats what happened to my olds.