HELP!!!! My truck has a missfire!! I can't figure out.?

[try_again41]

I have a 1995 chevrolet 1500 4x4. It has a bad miss when you engage the cruise control but no miss in normal driving. I also noticed that If i disconnect the timing bypass wire ( putting truck in base time) it Never misses even with the cruise on. But leaving it in base time is really killing my fuel mileage. I have replaced the ignition module and the ECM and still have the same problem. I have thought about the pick-up coil but I figured that would be a problem all way around. I just need some advice or maybe someone else has seen this problem. It also is electronic cruise control. Thank You