I have an 88 Wrangler with a 4.2 liter & 2 bbl carb. I recently removed most of the vacuum lines that were all over the engine as they were rotted and leaking. Since then I have replaced the original BBD electric carb with a rebuilt BBD non-electric carb from a 77 AMC pacer. I still can't get the idle right when it's cold and at about 3200 to 3500 rpm's it wants to start surging and will not pick up any more speed. I had the control module tested and it appears to be good. I also checked the timing per mfg. instructions. It was within spec as well. Any hints on what to look for from some of the more experienceed jeepers?