I'm kind of thinking its the mass air flow sensor, when my mom had her 02 ls with the 3800 it stalled once, fired back up no problem. After that whenever you would try to go to a passing gear it would start jerking like crazy, I thought it was the transmission also. On the way to the mechanic mom was driving it doing 45 and out of no where the engine jumped to 3000 rpms, then went back to normal. When we told the mechanic he checked and determined the maf was bad, replaced it and it never acted up again.

 

Nevermind my last post, I only read page 1, guess it helps to read all the pages before answering.