Engine Performance problem
1996 Chevy Blazer 6 cyl Four Wheel Drive Automatic 170k miles

Hi guys! I have a problem with the engine in my truck. It seemed to have rough idle for a while and now when I start it stays on for about 1 sec and idles real low, then dies, if I reverse it dies, if I turn a corner it dies. If I stop at a stoplight it dies. I cleaned the egr valve and I have been told it may be the Idle air control valve. Where do I start? What do I have looked at to figure this out. I'm completely cluless, let alone a chick who doesn't know cars well. Please HELP! Thank you.