On the 94 Camaros you can't read codes by grounding and flushing the aldl connector that ended in 92 as did the removable prom in the ecm...from personal experience.The connector for the TPS can be back probed if you use paper clips to extend the probes. Just remember, what ever route you take to measure, don't let the two leads touch each other. Check the attachment of the TPS sensor, if there are slotted holes, then its adjustable, loosen the screws and rotate. If it is not, you may have to bend the tab. The ECM will tell you if the TPS voltage is set too high or low.
ECM in the diagnostic mode should flash out code 12, if it is an OBD I.
The ECM without the prom is called a controller, the protector for the prom. On later models, starting with 1990(?), the prom is soldered into place. One has to remove the cover and see, it might be installed into a socket rather than soldered. You want to get the SAME part number of controller as OE installed. You have to transfer the prom. Do not change the prom on a metal surface nor on a carpet. Use a piece of wood and touch both metal chassis together along with yourself. Remember static electricity? I would give the chassis to an electronic friend and watch him do it.