OK I have a 1997 eclipse gs automatic 4 cyl and it shifts good from first to second but it will redline before shifting into 3rd if i disconnect the battery for a bit then it will shift good for bit

Have trans codes read. Probably your speed input sensor is going bad.

I have a code reader how do I do it there's no check engine light

Might have a stored code even without light lit up. Although un hooking battery erases stored codes on these cars.

Ok because I check codes and there was none and I checked before I disconnected battery

Unhook battery for at least ten minutes and try to drive it again. Right after it acts up check for codes again.

Ok I will try that