Tyler Dirden

iTrader: (3)

Long story short as possible:

94 Accord EX auto running well and only had a soft 3-4 shift.
Drove well the night before and the following morning I hopped into it and drove about 1/8 mile and suddenly had no gears at all??
Full of clean fluid, no engine or trans light, no previous noises or problems.

Removed at shop yesterday and replaced it with a known good trans from a 91 accord. Just for fun I decided to tear down the old trans and inspect it. It looked like a new transmission inside, every gear, bearing, shaft and yes EVERY SINGLE CLUTCH AND STEEL were in perfect condition. No metal anywhere?

I drove the car home this evening (110 miles) and had no problems at all. Went out to town and suddenly lost every gear like the last transmission, like it was in neutral? Shut it off, restarted it and drove it home but had to shut it off and restart it three times to get it home.

What could both of these transmissions have in common?
Is this a trans computer failure?
Can the floor shifter switch have anything to do with this?

Again, I found nothing wrong with the first when torn down and can not suspect the second one has a problem either. I have searched for two hours and found nothing of value on this matter.

HT can you advise me? I would like very much to replace the correct part this time.

MAD_MIKE

Check the basics.
Does the transmission have enough fluid?
Internal seals will wear out and not maintain fluid in all the circuits.
Best way to check is to let the engine idle, place the trans in every gear for a few seconds(long enough to feel the gear engage) and then place it into Park, pull dipstick, wipe, reinsert, pull dipstick and check where the fluid level is.

Verify battery is holding charge.
Being the trans is electronically controlled if the battery is dying it may cause strange electrical issues.
Verify the CEL and D4 lamps work. Check for any stored codes.

If the shifter switch is suspect, verify it makes proper contact for a given gear.
Verify the shifter cable is adjusted correctly.

Verify the shift solenoid screens are clean.

Verify the coolant is not mixing with oil or ATF from a leaking internal cooler.

Prior to the first transmission dying, was there any work done to the vehicle?
Recheck that work.

Tyler Dirden

iTrader: (3)

I have seen you post in previous threads and thank you for your time here too.

To all of the above, yes.

This transmission was just installed and had the torque converter flushed and the cooler prior and all new fluid.
There are no codes. Lights are working correctly after testing with a jumper.
No leaks as all external seals were changed before installation.
Exact correct fluid level checked multiple times as suggested as false readings are easy on these dipsticks.
When shifting, every selected setting produces a corresponding light change in the dash gear indicator that is correct.
ALL solenoids and speed sensors were removed prior to inspect screens and condition which was perfect.

About 3 thousand miles earlier the first trans was pulled to replace the rear main seal that was leaking. It worked perfectly (except for the soft 3-4 shift) until that exact moment and no codes or D4 light was triggered.


Just as I explained above, the original trans was without a doubt in perfect condition inside and every plate and clutch was inspected. This replacement trans did the exact same thing just 130+miles later??? I do not believe it can be a transmission issue from the exact nature of this problem. I have read multiple threads that have explained this symptom and never had it diagnosed. The majority of the posters just like saying "that tranys fried", which I have established is not the case whatsoever. So I think it has a TCM issue and pulled it this morning to inspect the board and nothing unusual at all to see and I have 25 years of electrical design under my belt.

I am toying around with the idea of hooking my O scope up to the shift solenoids to watch the wave forms and whatnot just to establish whether an electrical condition is really to blame as I believe.






Thank you for taking a moment here. I love these cars too much to just not understand this problem. I have another TCM I am planning to try and see if a non apparent failure in the original TCM can be isolated.

Tyler Dirden

iTrader: (3)

bump


This is a very common problem. How is it possible to not have a single thread with a related answer?

MAD_MIKE

The common problem when the trans goes to in-op is the sump filter is impacted with clutch material and the pump can no longer pump, thus the trans no longer functions.

Did you check the sump pickup filter on your original trans?

Have you verified pressure on the test ports of the 'new' trans?

Did you reuse your existing converter or did you use the one that came with your new to you trans?

If the trans is making a whining/whirring/low howl sound from the TC area when the trans no longer functions I am going to say that the sump filter is plugged and the sound is coming form the pump cavitating.

Tyler Dirden

iTrader: (3)

Thank you for trying here.

After I tore down the fist trans, I found no debris or clutch material in the trans or filter unit. Was hoping to actually and explain this away quite nicely.

I know of three to four ports on the trans but do not have any specific info as to the pressure readings. I do have very good equipment at my shop to read these ports if you can elaborate on the specifics.

I re used my first converter. I had it flushed after it was drained and every drop of fluid inspected for any matter. Zero debris was recovered and after it was bench flushed with solvent, I operated the converter stater and such manually to "feel" for any strange movement or condition. These checks were made on the second transmissions original converter and were identical in feel and resistance needed to operate the internals. I did not use the converter because the flywheel diameter was different than the one on my 94.


The trans is not making any noise that is not exactly like the noise that is expected from a fully functional 94 accord. Reason I know is I have 2 of these cars with the exact same drive line.

It is so very strange to have no gears whatsoever without so much as a change in sound or setting. The day before when driving home on the highway I was able to travel at any speed without issue and pass, downshift up hills, stop and go etc.. It just without warning stops having any gears?

I am thinking about hard wiring the solenoid lines into the car and powering them individually to see if I can obtain any results from the trans. I am not exactly sure if 12v is fine to apply as many solenoids have different power requirements that may be like 5v or frequency driven through duty cycle or such.


After all the years I have seen you post on these topics, I hope that WE may finally prove to have an exact reason for this condition and solve it.

MAD_MIKE

Honda ATs are low pressure units.
IIRC 120-130PSi, 110psi is minimal. R D1 D2 should maintain this pressure. D3/D4 with throttle valve closed will be ~70-75Psi with no less than 64-67Psi. With full operating pressure available at more than 1/4 or 2/3 throttle valve opening.

Few things that come to mind.

1.
Are the input shaft diameters the same?
Simplest way to check would be to verify the large converter fits onto the old transmission.
If it doesn't fit, possibly the shaft has rounded/sheared off in the car.

2.
The original converter is the problem.
Internal component(s) of the converter have failed, stator or otherwise.
May have 'checked out' via hand, but engine torque eventually 'refailed' whatever is no longer functioning again. Possibly when setting the converter down on its side a component reset into a spot that allowed it to properly function. This would make sense if the pressures check out good but there is no movement. Pump is directly linked to the engine via the TC case. While drive/power transfer requires functional stator and turbine.

3.
Faulty wiring, connections, or TCU.
Although I thought even when in a failed mode D1 or D2 and Reverse still worked, due to the shift solenoids staying 'OFF' the car could be driven in limp mode.

I'll look around for the FSM...

holmesnmanny

If the transmissions are doing the same exact thing then I would say it's either a tcu or wiring type of issue.

Tyler Dirden

iTrader: (3)

Thank you for the service manual.
I have a lot to look into now.

I have been thinking that the converter has the common link and maybe worth pulling the trans for a replacement. I have a bunch of checks to make on the pressure ports first and will post up when I know more. I have to tow this car back to my shop now.

DCFIVER

Try inducing a code and see if the TCU is capable of setting a code.



As for it being common,Ive not see it before, so I would have to start from the beginning here....

Tyler Dirden

iTrader: (3)

I think we have a success.

There were no stored codes in the TCU. I replaced the TCU and had the exact same symptoms. I decided to put the original torque converter into the replacement trans. I had to get an older 91 Accord flywheel for the converter to fit. I flushed the converter and was happy with the results.
I removed the trans once again to install the converter and flywheel in just three hours. I put in the new fluid and tested it out and it had no gears whatsoever once again. So I began to look at this without making assumptions. I had assumed this trans was good from the low miles and the giant hole that was in the motor from the thrown rod. I had this trans in my shop for 6 years and really hoped it was worth holding onto but I was having doubts now.
The first transmission that lost all gears was on my bench and I just couldn't resist cracking it open. After I went back to look it over a bit more because of the seccond trans failure I looked a lot closer at the filter assy.. The filter was layered over with a thin coat of that normal trans sludge but nothing substantial. I shot a spray of cleaner at it and found the filter screen media was very very fine and cleaned easily. The filter was blocking flow enough to reduce trans pressure and stop all functions from operating.
So I decided to clean the filter on the replacement trans. This is not possible without removal and disassembly, OR IS IT? I carefully examined the opened trans for an exact measurement of the filter inlet and decided to carefully drill a hole, tap it for 1/8npt and gain access to the filter inlet for flushing.

Remember, I had perfect shifting just the prior day with my entire family in the car. I had no reason to believe that the trans was just suddenly worn out. I thought it would be a last ditch effort for repair. After making a perfect mark and ever so carefully drilling a small pilot hole and NOT pushing so hard through as to puncture the filter screen. I drilled a couple more holes up to 5/16 then tapped it with a 1/8npt tap. It worked perfect. I looked into the hole and the filter was right there and with my camera I could see the very same sludge stuck to the screen. I got a long straw for the brake cleaner and shot the spray all up into the filter and watched a fresh stream of fluid come out that was stuck above the screen. I was very excited! This was working out and I flushed the case out well with air and plugged it with a new plug. I filled it up with new fluid and pulled it out of the shop and went for a drive. Every gear shifted perfect and never slipped or lost any gears. I was not at all able to do this an hour earlier, but after flushing the internal filter with this mod it instantly fixed it. I am not going to say 100% fixed until I put a couple hundred miles on it. As for right now, 10 miles in with perfect operation I am very pleased to have gained this result.
Here are some pics of the surgery I preformed on the trans case. It is very simple to do and if you are VERY careful when drilling through you will not have an issue at all I believe. From so many of these sudden loss of all gear threads I have come accross; I hope that this can be helpful.

MAD_MIKE

I am not too keen on putting a plug there as it is the lowest spot on the car up front and could easily snag and break the case on a bump. As it is the factory bolt bosses are ground down a bit from scrubbing the road. If you could find an allen screw instead for a flush fit that would be better, but I doubt anyone makes anything like that out of brass.
Adding a skid plate to protect it from snagging would be beneficial, but it would be more work and an added step during normal maintenance and oil changes.

I am all for an easier way of accessing the filter sump for cleaning as it is fairly small and a PITA to get to, but that whole area of the filter is the screen. It just has a tiny opening for sump/prevent starvation. I've thought of making a piece of tubing to insert in through the drain hole that would allow one to simply blast the sump clean. But have been too lazy to do so.

Tyler Dirden

iTrader: (3)

CRC makes an extended straw for their spray cans that has a sealed end and multiple tiny side sprayers that is 12" long. I use that for full penetration into the filter and was careful not to just poke it into but to rotate it somewhat as I was inserting it.
Sludge or not, it was just on the filter screen and needed some cleaning. In my experience with actual sludge formation it is always in the bottom of the pans on many transmissions and none was present in the bottom of this trans with a camera to view inside.

The addition of an allen style 1/8 npt plug is no problem as I have many and didn't think ahead to use one actually. The worn area on the bottom of the trans is not impact related though. I have had this trans for many years and have moved it around a lot by just sliding it here and there. I will indeed put a flush set screw into the hole though.

The trans is shifting fine and I have several hundred miles on the unit since the filter flushing. I am going to do this to my other 94 Accord BEFORE it comes to a fault. This is really easy if you get the hole just right. I just wanted to post a "Got it fixed" report for the forum. Thank you very much for your time and the information you linked me to.

johnsdm

I have a '98 Accord EX with the F23A1 VTEC engine and BAXA AT. The vehicle behavior I am seeing is it operates by starting with the AT shifter in 2nd gear, then sliding the shifter to D3/D4 once the vehicle is moving. Then, the AT shifts smoothly up to Freeway speeds. Reverse gear also works well. The vehicle is not engaging 1st gear when starting from a parked position with the selector in D3/D4/1. I am puzzled by this behavior and wondered if there are similar reader experience on their vehicle.
Background: The car only has 90K original miles, driven gently by a single person, but never having replaced the AT fluid. I have eliminated various check engine light OBD-II codes by replacing Pressure Sensors 1 & 2, Shaft Speed Sensors 1 & 2, Linear Solenoid, Lock-Up Solenoid, the two Single Shift Solenoids A & B, Both O2 sensors, Thermostat, and Engine Coolant Temp sensor. I cleaned the PRNDL Shift Switch and tested for continuity between each gear position. I have cleaned the screens in the Linear Solenoid and the Lock-Up Solenoid. Basically, after 20 years, all sensors that provide input to the ECM for correct shift points, engine performance, and transmission sensing needed replacement and cleaning. I drained and filled the AT fluid 4 times, to remove sediment and wipe off the sludge collected on the magnetic plug. Some amount of the GM Dextron AT fluid was used by the previous owner to top off fluid, but that is all removed and the AT fluid is cherry red clean, as seen on the 4th fluid change. When having an inspection done at a local reputable transmission shop, their opinion was that Dextron would affect shift behavior due to fluid characteristics, but that's all. I have had first gear engage sporadically while test driving, but only following a AT fluid drain & fill. Otherwise, I need to start in 2nd gear.

Question: I am wondering if the internal screen discussed in the original thread post is the fault causing low fluid pressure on the 1st gear clutches and not allowing enough clutch pressure to engage 1st gear from D3/D4/1. All other clutches in the AT work from 2nd, 3rd, 4th, and the TCC. Another thread I wanted to investigate is whether there is an electrical, TCU, or mechanical linkage to investigate. The overall behavior I am seeing now, is that the first gear does not show a sign of engagement. When shifting from P/N to D3/D4 or 1st, I hear a sound once, which sounds like there is an engagement of the gear train, but then there is no forward motion for any level of throttle input from 1000 to 3000 rpm. Shifting into 2nd gear is definitely solidly engaging.

99stockcivic

Personally, sounds like a clutch pack, not related to the original post.

johnsdm

Yes, that is the feedback received from the Transmission shop, 'classic Honda worn-out clutch' behavior. But, accepting that answer results in a $3K repair bill.
What are your thoughts on the ease of rebuilding the transmission? There is a local garage that rents out lift space in enclosed heated space with tools and consultation available.

99stockcivic

If you have some mechanical skills, I would attempt it at that price.

However, it really depends on your skill and comfort. If this is your first transmission, you will probably make some mistake where you have to take it apart. I think, on average, a person who has never done it before ends up taking it apart 3 times before it's right. If you have the time, its'a good skill to learn. However, if you are not mechanically capable, then don't do that, it's not like changin an oil filter

Also, if you want another suggestion, and again you are mechanically inclined and have the space, then I would consider just buying a used replacement. You can get a JDM replacement for $500. Just swap the shifter solenoids over from your current one and be on your way.
https://www.ebay.com/itm/28384891878...kAAOSwJiRel8Dt

Then all you are doing is pulling and replacing, something you can do over a weekend. Just drops through the bottom.

I wouldn't spend that kind of money paying someone 3k, but that's me. I swapped mine when it needed it, and it was pretty straightforward. It's again, not simple like an oil filter, but it is something a person can do in their garage.

bloomin

Wow this is a brilliant thread, although I don't have any problems yet with my 1994 Accord LX automatic I will keep this thread in mind if I come upon similar issues in the future. Luckily this car
which was originally my Mom's car had the ATF changed out on a regular basis for it's entire life now, and it is said that it's important to change it in the early years because this is when the majority of
clutch pack debris builds up because they are very new relatively.

Thanks friend!

MAD_MIKE

Doubt it.
If the main sump pickup was clogged, you would have no operation in any of the gears.
Most likely the accumulator for first gear is done or sticking.
Can always try a last resort of adding a hydraulic system cleaner(seafoam trans-tune, etc) and see if that will break down any varnish that may be causing a hangup. But if the spring or seal are toast then it only works on occasion.
Hard parts are not a problem, its the valve body, you will more than likely need to go through that, Check out Sonnax for the various kits for those to give you an idea of what needs to be done.
Trans can be pulled from the bottom, on a 98-02 you might have to pull the front beam out for more clearance but not sure. If you have a garage large enough to contain the car you will have enough room to pull the trans. Do you have an FSM for your car?
Link in my sig has a rundown of how to do remove in a 94-97, 90-93's are very similar, 98-02 will be slightly different.

xycarta

Hi! How is your "Got it fixed" report after theses years? Is your transmission still ok? Have you cleaned the filter many times?

MAD_MIKE

I can't speak for Tyler, however, once there is access to clear out the filter screen, there is no excuse not to pull it and verify the screen is still clear of material.
Since this is the only area where junk may be pulled to, it is a good idea to remove this plug while servicing to verify the screen stays clear of junk.

xycarta

I would like to thank Tyler Dirden

Just did the hole trick to clean the filter on a 7th generation honda civic 2005 with success!

I also told about the procedure to another civic 2001 owner who also repeated the procedure.

I already drove 1000 km.

here are some videos
https://www.youtube.com/channel/UCXC...SU4lyvyz2dvYvQ

If someone needs tips, just leave a comment in the videos.

Vaqas1

I have a Honda with S4MA transmission and its whining badly especially on Park. Its 19 year old transmission never rebuilt before. We suspect this filter screen to be clogged can we use same method of drilling hole on same location for this S4MA transmission location will be same?

xycarta

We have done this on Honda Civicsin Brazil. But cleaning wasn´t enought. We kill the internal filter, and add an external filter. So far we had success on 22 cars. My whatsapp +55 21 98111 0009 for help.

99stockcivic

Before doing that, are you 100% sure the fluid is at the right level? If so, have you changed it recently?
If not, it can't hurt to drill and clean it, but I am asking so that you do the basics first.
And, if it still whines after you do all of the above, I would guess it's time for a rebuild. If that's the case, you can get a used one from Ebay for about $600, that's probably cheaper, and you can usually install these yourself, depending on the vehicle.