92 accord ex, 126,500 miles, auto, CEl im guessing bc speed sensor is out [speedometer is not working].
The transmission won't shift out of 3rd gear. Just had full tune up. The D4 light is always on.

Maybe the transmission filter and transmission fluid flush?
Bad TCU?
Or just blown transmission?

Any solutions or advice?
Price of the transmission to be dropped and fixed/or replaced?

No mods either.

 

my girlfriend had the same problem with her 92,i tried almost everything,except switching the tranny. eventually i gave up and made her sell the car. check your fluid level and dipstick for metal shavings? my guess is the trans. is bad.

 

Get the codes, all of them. Sounds like you have Engine and Trans codes. Jump the connector and count the flashes from the CEL and D4 light.

 

If D4 light is always on...even in park...that's your signal for a tranny prob. From what I understand, the speed sensor only affects downshifting. I'm willing to bet that it's a bad TCU. They're known for leaking capacitators. Try disconnecting your battery or pulling your radio/backup fuse for a few minutes. If that helps (would only be temporarily) it's your TCU.
As poorman mentioned...jumping your connector should make the D4 light flash...counting will give you the related trouble code(s). If you do some research there's also a couple of checks you can do while driving and shutting off the car over a certain speed to see if that temporarily fixes the prob, but I can't quite recall the actual procedure and that sounds kinda shady to me personally. Good luck.

 

Its used to fix the transmission when i would disconect the battery for a few minutes. Will try again and repost.. Thanks for all help