I got my hands on a 2000 Buick LeSabre with the 3800 V-6 that seems to be OK for the most part except this annoying problem.

Starts and runs fine when cold. Will run all day long if started cold. Shut it off and let it sit for 30 seconds after it's warmed up and the problems start. It will stumble, usually die, but not always. Sometimes it stumbles a few times and then clears up. If you give it gas while it's stumbling, then it dies out. It will restart but it is difficult to do so. Then, after restarting, coming to a stop will usually cause a stall.

It's throwing an evap system code but I doubt it's related. I know the ignition module is usually suspect here but it seems more like it's starving for fuel, though I could be wrong.

Anything common with these that I should look for?

It definitely sounds like the Ignition Control Module is failing, to me.

Ok, thanks. I will try one and see what happens.

I replaced the ICM and it still has the same problem. Will a Crank Position Sensor give these kinds of problems?

Try and get your hands on an advanced scan tool, which can display pending codes and has Mode 6 and Mode 9 capabilities (e.g. Actron CP9580). It may clearly show where the problem is. If that is not in the cards, I would focus on the MAF Sensor; MAF Connector; coil packs, which may be breaking down under load; Crankshaft Position Sensor, and Camshaft Position Sensor.

If you end up replacing the MAF Sensor, stay away from remanufactured components. My experience with them has been awful.

I remember the 90's when I was an auto-tech and I can't tell you how many times I replaced a MAF and had to replace it again because it was junk.

The only codes I get on the car when it is scanned is P0449 and pending P0449.