Engine stalls after WOT
 

My '98 Z28 seems to be stalling after wide open throttle. I get on it (to high RPM), then depress the clutch and release the accelerator to coast and slow down. The RPMs understandably drop, but drop too far and the engine stalls. I have to dump the clutch or restart the ignition to get going again. This has happened a few times.

Also, at idle, occasionally the RPMs would drop and almost stall - the interior and head lights would dim, but the engine would still run.

I did get my computer reprogrammed by ls1speed inc. I don't know exactly what they did, but I didn't really notice this issue until the reprogramming AND after the car sat unused for 3 months. Any ideas?
:bang:

Maybe the computer needs to relearn the idle.

Do I just do a few start/stop cycles? Or do I need to program it?