sefiroxx

Most gm designs have fans on when ac is on. Did you check the charge using a full set of guages? You need to monitor both low and high as well as compressor status when the system is on and when it starts to blow warm

Invest in the tool bag. Various extension lengths, wobble extension, stubs for side wrenchb usage

The tps is a variable resistor. (Ie, closed: 0 resistance and all voltage returned, open is high resistance and half the voltage is returned.) If the wire harness is failing, it will induce additional resistance on the voltage signal Check the circuit at the tps, the pigtail, and back at the ecu.

Use a scanner and pull codes. Post them with their descriptions (no one has memorized 100's of codes)

If the problem always occurs when down 1/4-1/2 then it's a float problem.

Check the tranny fluid as well. Things maybe starting to go.

Try Cleaning the throttle body and butterfly. Monitor STFT to rule out any lean/rich scenarios

2 suggestions. 1) ac off, fan on. Do the symptoms come back? If yes, then water got in the air intake to the blower motor. If not 2) compressor clutch coil circuit probably shorted out. Probably was a tiny, low amperage short but the introduction of water might have allowed plasma arcing and this increasing the dinosaur Amperage flow. Pull the fuse, relay for the clutch and see if the symptom remains

Probably a common ground point.

Sloppy - probably leaking fluid at various points and likely In the accumulators. The hd2 should help. The hd2 does not have accumulator pistons (the pro kit does). You can find the piston here https://transgo.com/product-details/4l60e-accumulator-pistons/

Pull codes to figure out which component. Probably wheel sensor or its site harness

I would have recommended buying a remanufactured and upgraded babe body. The early valve bodies had a few problems like weak springs and plastic accumulators. You should replace those, and install a new separator plate to get check ball holes back to spec. Since it's 20 years old, triage the solonoida and the internal wire harness to play it safe.

To be safe, follow electricians training and rules, you should cut off all the damaged ends to get to good clean bright copper. If you do that, the cable might not be long enough. The terminal then needs to be crimped on, with a significant amount of force, which you might not be able to do up under the wheel well. I recommended running a new wire.

Power steering pump? Check fluid.

04 Sierra. A lot of stuff on the dash like masks, bandanas that interfere with the ALS. Try cleaning or replacing. I use the dial on the left side of the dash to turn off the auto mode and kill the lights at night when needed.