Thank you for your time and consideration. I can see by your question, you needed more info before a proper diag. Could be given. However, I discovered the problem with information from my dad. Non-Vented Fuel Cap! One other "GURU" told me the code 12 was a bad computer. And that "NO MATTER what anyone else told me, change the computer." My book says a code 12 is: "No distributor Pulse present". We checked and checked the result was the same. The non vented cap was allowing too much pressure in the tank for the fuel pressure regulator to send fuel back to the tank therefore not allowing sufficient or any fuel to flow through the fuel rail. (This last part is assumption reasoning) We took off the cap, ran fine. Put the cap back on ran fine for a while then died. We repeated the process twice more. Same results. This is just the result we found with MY Camaro. It may not be the same for any others with the same problem. But I would check it out before I would condemn the computer or fuel pump or coil. Thank you for your time anyway.
Updated 2-15-10
It seems that a single injector on a particular bank can cause an intermitten engine problem. I can't be positive about it as each situation can be different. I did find that one of my injectors on the left bank was bad. When I replaced it with a new one, the engine started with no problems. I did check the computer with a known good one and there was no difference. I also replaced the fuel pump. No change there either. The only thing that helped was changing the injector. Thank you for your help. I thought I would share this info with you just in case it comes up again.
Monday, January 18th, 2010 AT 11:10 AM