Your symptoms sound exactly what a dodge truck was doing that I had in my shop. A tranny shop had replaced the plugs because they were as black as can be. No worky. Plenty of smoke pooring out the tail pipe. OBDII threw every code it could. Went so far as to pull injector rails one side at a time to watch the spray. It acctualy ran better! Pulled the cat off, ran water threw it and all the pretty platnum came pouring out. Replaced the cat, start it up , cleared it out and ran fine. The dealership diaged it and said it needed a motor. ( I geuss they figure replace the weak link )
Try to unbolt the exhaust down pipes and fire it up.

 

Yeah, did you pick up the stuff I listed? You'll have to find the service port on the fuel line, not sure where it is on the Camaro, since I haven't ever had to fix a fuel system on one of these, but they're all pretty similar. It should come up the drivers side, if I remember correctly. You'll wanna hook the pressure gauge to that service port (when you screw it on, wrap a towell around the line so you don't spill any gas.) Let any gas you might have that the towell didn't get evaporate, which should only take a minute. Start the motor up and let it run for a few seconds to get your regulated pressure. Pull off your fuel pump relay and jump the power line to the pump, that would be the terminals with the two largest wires. This will give you unregulated pressure. From there, hook up a drain port to the gauge, and run a hose from that to a container that can hold at least 1.5 pints. Run the pump for 30 seconds, you should get almost exactly one pint. You'll use this gas for the alcohol contamination test. This is where the graduated cylinder comes in. Pour 10 ml of water into the cylinder, then fill it to 100ml with gas (that would be 90 ml gas, 10 ml water) pour that into a clean, dry sealable container ( a cleaned out glass drink bottle works well) shake for 30 seconds, and carefully pour it back into the graduated cylinder. The water and alcohol will settle to the bottom (they'll be clear) and the gas on top (amber) look at how high the clear is, and divide the difference by the remaining gas. For example, if the clear is at 13 mil, you have 3 ml of alcohol, and 87 gas, so 3/87 is about 4% alcohol. Anything up to 10 percent is safe for the car, over 15% and I would scrap the gas and refill the tank. It's not likely to be the problem, but I've seen it happen once, which means it DOES happen, and it only uses like 50 cents worth of gas.

 

Madmike, the cat has previously been removed. FTiger, thanks for the info. I'm having trouble locating a fitting with the test port that goes between the TBI unit and the pressure line. Local supplier wants $60 plus shipping and I'll probably use it once. I do have the rest and my test gauge does have a drain line. I'm printing this info you supplied because this is good future reference. I'll come in handy for vehicles that sit for awhile. I'll do the test once I've got everything. Thanks again for your replies.