jumpering the connector and the vehicle running better is a good sign. I haven't seen this problem personally in over 10 years. as i stated before it is part of my TBI tuneup "recipe".

i made a...

D1984A is the "369" module
D1945A is the "048" module

369 is the one to get. apparently gm discontinued the 048, so i've always wonder if both Delco numbers are the same module but never had the...

sounds like you don't have equipment to data log? if not try to jumper the terminals of the CTS together. start engine, within ~30 seconds you should get a code 14. If you do, the wiring to ecu...

Was it a code 15? do you have a known good coolant temp gauge to confirm the engine was up to operating temp? sounds like the CTS is bad or there is some wiring fault on that circuit. datalogging...