mrwipemedown

I just bought an automatic 1992 Honda accord LX. I bought it knowing I had some issues to repair on it, and I am a auto technician currently at a toyota dealer. I have talked to a few people and they think my issue is a AT ecu.

The D4 light in the instrument cluster doesnt blink like they normally do when there is a issue, it stays solid green all the time, even in park. When I shift to D4 and accelerate, it always starts off in 3rd gear and will not shift into 4th and doesnt downshift either. If i manually move the shift lever to 1st, it WILL go into first and accelerates fine. Once i go to shift it into 2nd manually, it jumps straight to 3rd. moving the lever to 3 or d4 doesnt make any change and it still stays in 3rd. I hope it is a AT ECU issue (maybe why the light is constantly on?) and not a tranny problem. It does have 165k miles though. Also, i have hooked up the jumper plug and the light did not flash. One time I turned the key on (checking something with the AC blower) and the I caught the d4 light flashing a few times but it hasnt done it since. Any help would be appreciated, as I am not that knowledgeable of auto trans issues. Thank you!

alkoholikwun

try a new TCU, ive also heard that a bad VSS can cause this, not sure why it wont blink though.

also saw somebody say this on cb7tuner.com

"The only reason that it won't down shift is because the ecu reads the VSS to establish weather it is safe to do so or not. If the VSS reading is too high for the selected gear it won't engage it, to prevent idiots destroying the trans and then blaming Honda."

mrwipemedown

It has no codes though, wouldnt it set a code if it was going into limp mode?

Any other ideas? I dont want to buy a $140 reman ECU on ebay to find out I need a new tranny or something.

P_Adams

There are two sets of shift solenoids which mount to the case. They are sealed to the case with rubberized gaskets which incorporate filter screens.
these sometime cause a blockage from contaminants.
I would suggest having the solenoid packs removed, checked for either open circuits or internal shorts, clean the screens and reassemble if the solenoids check out.

P

mrwipemedown

Ok ill try that tomorrow.

If that doesnt take care of it, which computer should I order? There are so many different options on ebay, ones with lifetime warranty, etc...and I dont know which to go with. Some are used in working condition, but could they fail anytime (and I think its sold as is)

Or do you guys know of a better idea or a place to send them out to rebuild them cheap? Thanks!

phootbag

Pull back the carpet by the passenger feet and check for blinks from the tcm.

mrwipemedown

Already did all that, no codes or lights flashing

phootbag

Are you sure it was in 3rd? The manual valve ( connected to the shifter ) forces a gear selection. In 2 position you will be in second. I suspect a range switch or range switch wiring issue. Do other position indicators illuminate?

mrwipemedown

its always in 3rd, at least Im pretty sure it is for these 2 reasons:

When I manually go into first with gear selector, and take off, it accelerates normal and if i move it into 2nd it shifts but RPM drops like crazy. Kinda like when you shift from first to third in a manual lol, so yes I think its 3rd. Doesn't sound like the normal first to second shift.

Other reason is that ive driven to work on the highway in the gear its in and gone about 70-85mph and not redlining it lol. RPMs are high but I think its around 3 or 3500 at 60mph. Over 4k rpm at 75mph. And ive hit 90 before, I doubt second could hit 90mph in this car.

vonhonda

Where can I get new gaskets for the solenoids if I clean them and find the gaskets need to be replaced?

siavosh

I have a 93 EX with the same problem. It happens at random and so far only three times in one year but I really want to get it fixed. Try this link I found a few weeks ago. I know you said you are not throwing any codes but this might be helpful.... http://techauto.awardspace.com/transmission.html

siavosh

Make sure to read the whole thing. It is a really good write up with images and all possible scenarios (solenoids, relays, TCU...). The rest of the page is really helpful as well but the link goes directly to their "transmission" troubleshooting section.