Transmission problems

[Dou123]

This sucks guys i really need your help becuz my transmission will not shift at all from 2nd to 3rd. HEre is the dillema its an automatic which starts off good in frist then shfts to second then jst sits and revs while im going down the road it grabs but barely and its like the computer or rather the tranny doesnt know what to do. i have put it in revers before and i strted rolling forward lol. i need help and bad cuz i wnt to sell the car or evn keep it if i can figure out the problem. it hasnt been doing this always it jst recently strted doing this and getting really bad once i got my new exhaust put on. i know i should put a 5speed in it but i wnt to buy a motor for my mustang first if i can fix this problem quick without a new tranny. i was reading up on other trannys and problems similiar to this about how it wouldnt shift and then they looked at the wiring harness and something wasnt connecting right or somehow got burnt and was shorting themselves out so do u u thnk that could be causing this? ne help would be greatly appreciated guys thnk u so much. Peace.

 

~UGC WINGMAN~

[Hatch92]

if you put it in reverse and it's goind forward then you have a synch issue. when you move the shifter your missing or over shooting what gear you want the car in.

[Dou123]

Well if thats the case than wats the fix besides a new transmission if there is one. i am thinking when i did my lst tranny flush i overfilled which could cause that wouldnt it because the way the transaxles work it would build up more pressure causing it to go further thus landing not in a gear at all? im jst assuming from what i read in my chiltons that would make sense. let me know what you think thnx for the info.