Hit the jackpot at Advance Auto...
Turns out this kid is some sort of LS1 whiz. He's had several Fbodies, him and his gramps built a 9 sec Trans Am last year, and he's currently on the waiting list for the new Camaro.
Together we fixed my problem right there in the parking lot, and he let me return a $133 IAC valve that I bought last week cuz it turned out to be not the problem.
How lucky is that????
Went back to square one and found a stubborn throttle cable.

