93EX auto shifting issue

[Cautrell05]

Need a little help, have a transmission question on a 93 EX automatic, 229,000 miles. Quick background on the car. It had 170,000 on it 3 years ago when I got it. Always shifted ok, never touched the fluid. It was always full, didn't leak and bright red. The only issue with it was the converter clutch. At highway speeds when most automatics are locked mine is always unlocked. If i lean into it a little bit it locks up and unlocks right before it down shifts. This morning for some reason it wouldn't shift into 4th. Felt real sluggish from a stop like it was starting in second. Default I'm guessing. Didn't have time to go back home and get my other car so i limped it to work. At highway speed it spent most of the time in 3rd occasionally shifting up to 4th for a little bit. If i manually pulled it down to 3 it was still in 3rd but 3 and 4 were both lit up on the dash. Sometimes they were both on. Sometimes it went out. After about 10 miles it shifted into 4th and then the converter locked up. Pulled it in the shop at noon to pull codes and with the connector by the glove box jumpered and the key on i get no flashes. Drove it for 5 miles and it shifts normal plus the converter now locks up like its supposed to. I'm supposed to make a 280 mile trip with it Sunday and am a little concerned to be honest.
Any ideas?

[spiderpig]

Drive it till it dies..... sad but true this sounds like a AT going out too me

[emosun]

At highway speeds when most automatics are locked mine is always unlocked. If i lean into it a little bit it locks up and unlocks right before it down shifts.

That one should be easy. Mine did the same thing for years.

Adjust the kick down cable on the transmission , basically the car thinks your foot is pressed on the pedal harder then it really is so it won't lock up.

This morning for some reason it wouldn't shift into 4th. Felt real sluggish from a stop like it was starting in second. Default I'm guessing. Didn't have time to go back home and get my other car so i limped it to work. At highway speed it spent most of the time in 3rd occasionally shifting up to 4th for a little bit. If i manually pulled it down to 3 it was still in 3rd but 3 and 4 were both lit up on the dash. Sometimes they were both on.

Again we share an issue. Usually when the D4 light stays on it means bad tcu. If you have never taken yours out and checked it , now would be a good time to look for a burnt motherboard.

Although a replacement tcu at a junkyard is only 20$ and they're going to constantly break the older they get so pick a couple of them up. 22 year old computers have a hard time after so many years in use.

[deevergote]

Is the D4 light on? Did you check for error codes?
The D4 light staying on indicates a TCU error code. It does not always mean the TCU is bad. More often than not, it means the TCU is functioning correctly. Don't kill the messenger. Pull the error codes and fix the problems. Replace the TCU as a last resort.

[Cautrell05]

The D4 light was on most of the way into work yesterday. If I pulled it down to 3 D4 stayed lit up also several times. With it in D4 and cruising 60mph Sometimes the D4 light would go out all together for a second or two. I didnt have time to check for codes before work. At lunch when I checked it I didnt get any codes. Does it flash anything if there are no codes? No flashes or anything. Shifted fine all the way home last night.

[deevergote]

It should flash if there are codes. Codes should be stored, even if it's not on when you check.
Are you checking properly? Key in the II position, with the service connector jumped?

If so, then it may indeed be the TCU.

[Cautrell05]

do the codes clear when the ignition is turned off? Some of the older fords did that. Had to pull codes that same ignition cycle.

[Cautrell05]

Anybody?

[Accord problems]

mine did this where i replaced the shift solenoid then the lock up solenoid . turned out to be a faulty tcu . that would also cause sluggish take off and not properly shifting as well as poor gas mileg .

[Cautrell05]

Well the mileage has sucked for a while even when it was shifting fairly normal. 21 tops. this morning it did it for a bit when I left home. ran for a while in 4th converter locked like its supposed to be. after about 3 miles it dropped to third and stayed there for another 4 miles. pulled over and tried to pull codes and got nothing from the transmission. check engine light came on when I jumpered the connector so I know that the wiring is good. D4 light comes on with the bulb check at startup. starting to suspect a TCU. Im a little hesitant to throw one at it though. I work in a GM dealer and have seen many times where something else makes the module look defective. Dont have any honda experience though.

[Accord problems]

you don't half to through one at it ? just take out the old one and look for goooo . blown copasiter's . clouddasc has a grate right up on this DIY: 90-93 Tcu Fix .

[Accord problems]

any luck?

[Cautrell05]

For whatever reason it decided to stop being stupid and go back to working like it has been for the previous 60,000 miles. No idea what happened.