My rpm gauge starts jumping up and down like crazy and then the car slips out of gear and back into gear and bucks terribly. The mechanic has tried all kinds of options, e.g. cluster, etc. they are looking to try a new halter? Anyone else but me have this problem? I can't associate it to any temp change; it does have 130K miles on it, a different engine in it. Do I keep it, sale it, help?

 

What is a "halter?"

Is the tach jumping in response to the engine RPM changing?

Manual or autotrans?

If auto, what color is the trans fluid, red, black, jet black?

Does the car do this in all forward gears? Howabout with overdrive off, or the trans locked in 2nd gear?