So a month or two ago, I started noticing a whistling sounds when stopped at a light/stop sign and also in reverse. My dad immediately pointed to vaccuum lines (307) and I found that the T-connector from my transmission line had an open end. So I bought some hose, patched it all up, and with the extra I got rid of some near death dry rotted lines. It was all patched up and pretty; However, upon taking it for its test drive, the shift between 1st and 2nd started causing issues. Now the best way I can describe what happens is as if the engine loses power in a wavy pattern like it’s powering down and back up, similar to the way an A/C unit in a home might dim the lights and make a wavy sound since it’s an electricity hog (hopefully that’s an analogy that people can relate to?). It will only do it on the first shift. 2nd to 3rd is normal. The solution I’ve used up to this point is manually shifting through my gears. Because the problem doesn’t occur manually I would assume it’s a trans automation issue and not the vaccuum lines...? But I could be wrong. My guesses have been torque converter and my dad mentioned the governor. Any insight?

1983’ Delta 88 (307)
TH-350