Hi, CSWill; Sounds as if the engine is being flooded. You mentioned that the temp sensor is disconnected. The PCM needs the information from the sensor to control fuel delivery. If the engine is cold, it requires more fuel. As it warms, the need for fuel decreases. Especially, on GM's, when the temp sensor takes a dump, it will default to -41 degrees (F) and cause the massive overfueling. The engine oil is surely contaminated with fuel, by now. The PCV system will send the fuel vapors into the TBI and just make things worse. By 'floorboarding' the throttle, it shuts off the flow of fuel for that moment, allowing you to start the engine, but.....
The first things I'd do would be to change the oil and filter (so you don't have another explosion) and replace the CTS. If you have a scanner, you can 'see' what the PCM is seeing as to engine temp. Compare it to the ambient temp. The spark plugs are probably fuel soaked, also. May have to remove, dry, and reinstall after about an hour while letting the cylinders dry out. Compressed air into the cylinders will speed up the process. I've even disconnect the ignition (no sparks) and cranked over the engine. You'll see fuel being spit out. Watch for fire, of course.
Good luck.
Loren