Lumina hesitation when warm

I have a 1996 Lumina 3.1 liter. I can start the car when it’s cold with no problem and it runs smooth. I can start the car when it’s hot (only shut down a few minutes) without a problem. The problem is when the car is hot and has had 15-20 minutes to sit, when I start the car it runs very rough…lots of hesitation and low power. So far it hasn’t stalled when doing this. If I get onto a road that I can get up to 45-50 mph it will straighten out within a couple of minutes and run smoothly again.

Any ideas on what might be wrong? I took it to my local auto parts store and had it plugged into their computer. They couldn’t find anything wrong.

Thanks in advance,
Jim

It sounds like a slow/sticking EGR or IAC valve to me. Try taking the egr off and cleaning the carbon out of it. Also, remove and clean the IAC valve on the throttle body (and the passage in the throttle body it rides in) and see what happens.