Newbie- Machine Stops or Runs Away

[mw569]

Have a 94 6030. During a standard lace program, machine will either stop or just runaway in X. The runaway is just a crawl. The only way to stop it is e-stop. Once you take e-stop off it starts crawling again. Slide hold does nothing. Have to power down and it fine for awhile(maybe days) This doesn't happen all the time. Have had a service tech out twice. Replaced a resolver on X first time (it was definitely bad). Still did it a few days later. Second time they came out, tightened a few wire connections. There not sure. Can't make it happen while they are here. Can't afford more of the same. The error messages are X motor overload #3 or #12 or #14. Motor is not hot. Has never occured during a Z level cut. Maybe just a coincidence. Slowing feeds down have made the problem less frequent. But still there. Any suggestons?