I searched through the FAQ and did some googling, but found no answer to my problem. I picked up an 83 GS last week and finally got it home today. It drove great over the 300 mile trip I had home, except I was having trouble going uphill, would start surging and acting like it wasn’t getting enough fuel. Topped off and the next hill I hit, same issue. Okay no big deal. Replaced the fuel filter and that issue is gone now. But I noticed while cruising through town if I try to speed up my car basically stalls or cuts power and as soon as I downshift it comes right back. It doesn’t die or anything, I just lose my momentum and rpms tank. I’m terrible with describing things but I hope that’s enough for you guys to maybe help identify what my issue could be... here’s what I have tried so far:

-cleaned spark plugs, weren’t to bad but I have a set coming in tomorrow to put in.
-fuel filter
-tuned carb using guide I found on here (I assumed that just maybe it wasn’t getting a good fuel to air mix and higher rpms were causing the problem to occur)
-checked a vacuum lines off of intake

everything on this car is stock. If that helps.

 

Welcome to the board.

My first thought is to ask if the secondaries are opening. In the event you have no idea what I'm asking - are you getting a surge in power at around 3500 to 4000 under acceleration? If not, then they are probably disconnected.