Hi

Have searched high and low and found lots of help but no fix...

First start up and when you put the car in any gear, it seems fine, no slipping, no strange noises.

After a very short time, you lose everything and the car acts as if it is neutral. Shifting to any other gear does nothing. If you shut the car off for a few minutes OR longer in some cases, and restart it will repeat the scenario.

This same issue happens no matter what gear, even reverse and low.

After checking out Solenoids and the control module I am happy that that is all working. All dash lights behave as expected with no warnings (unless you leave a solenoid disconnected LOL ).

As the oil was topped up late at night when this first happened, I checked and found it high.

I have dropped some fluid and added some more...... but is now lower that it was but at the high end of the range.

I have also found that it not does not work more often than not ???

Findings:

After idling for a while and trying many things, I checked the oil line hoses and they were cold !!!!

I let it sit for a while and tried again... When standing over the motor / transmission area; at start up there appears to be an interesting whirring sound and after a while it stops. Have yet to confirm but seems to last about the same time as the system would work....

OIL pump fail or is there another valve in the path that is blocked / closed / not operating correctly ???

 

This seems to be a common problem when these trans fail in this manner. Works fine, then after 10mins the trans acts as though it is in Neutral.

My theory is that this mostly occurs on transmissions that have not had the fluid changed in ~200K miles. All the sludge, friction material, and metal has turned into a grey slurry at the bottom of the sump. Finally there is enough of this goo to plug the screen/filter of the sump. The whining is the pump not moving fluid due to the blocked sump pickup, and hydraulics cannot work without a moving fluid. Thus the port becomes blocked and no work can be done by the trans. And since our cars do not have readily replaceable elements, without a rebuild, we are stuck.

If you can, park the car where you can drain the trans fluid. Pull the drain plug and wipe it off, if it is covered in grey goo and metal then the trans fluid has been neglected for some time. Buy three, gallon jugs, of Dexron II ATF. Doesn't matter what brand it is, the cheap stuff will do. And two cans of Sea Foam Trans Tune...


Drain and refill three times in the normal fashion.
Before adding the last quart of ATF at each refill, add 8oz of Trans Tune to the case. Let the car idle and circulate the new fluid, then place the trans through all the gears for a few seconds to make sure that each circuit is charged with new fluid.

Take note of the color of the fluid coming out, if grey slurry is being removed at each drain, progress is occurring.

FWIW, my '95s trans did something similar. Would work fine, pressure was fine, but after a few moments of goofing around the car would act as though it was in Neutral. I had a pressure gauge and it would just drop. At the time I did not know what was going on exactly. I purchased a low mileage Japanese unit for a few hundred and just replaced it.
However after draining the old trans of slurry, and opening the case I found nothing really wrong with it other than the internals coated with goo. It was a combination of my ignorance and negligence. Had I properly flushed the trans I am certain I would have not had to change out the transmission.

*Although the Odyssey transmission, with its lower gears, that replaced the failed one is MUCH more fun at the stop lights.*

 

OK - Flushed and used another bit of advise and removed the cooling hoses and watch the crap come out while adding new oil.

Went from a dark murky colour to something much better....

Let the car sit and then ran through the gears - at each change one could feel the drive working.

Let sit for 1hr and then went for a drive around a few back streets and went through the gears... Maybe 2k and after 5 min I though - FIXED.

Pulled up at a coffee shop and had a coffee and a smile.

Jumped in and away we went and then not 150M down the road loss of power. Manually selected other gears and nothing... coasted to a stop. Turned off and checked for leaks / and oil level. Looked OK. Started and had power but only got 200M. Let sit again for a min with engine off. Started up and got another 200M. Same deal again and after 2 more attempts got home.

Better than what I had yesterday BUT it seems that as the system warms up or starts pumping - something is failing. No lights flashing, no limp mode....

How to force limp mode ?????

If that engages but then fails after a while it has to be a valve / oil pump failing. Have looked and searched and can find lots of references to the modulator valve / pump and to test... "Troubleshooting the solenoid and the modulator fluid pressure"

But do you think I can see / find the plug to fit a gauge !!!! (Getting old and poor lighting / access. )

But starting to look like the pressure regulator is sticky or oil pump worn or binding.

 

The problem with this method is that you are using the sump/filtration to pump out the old fluid. Although it makes it faster you need to remove the goo from the sump. It has to drain out through the plug. When using the sump to drain you are sucking all the crud out of the sump into the filter.

Did you pull the plug? What did it look like?
Were you able to purchase any Trans Tune?

You can't force it. The AT is a hydraulic piece of equipment, if there is no flow or pressure it cannot operate.

Check the 'techauto' link in my signature. There will be a menu in the upper left, click on 'transmission' for detail on where the pressure ports are.

 

Trans Tune - None here in Brisbane Australia....

Limp mode... Sorry, thought that if a sensor was unplugged etc or the solenoids were unplugged it would go into limp mode. Must read the manual more closely.

I also did drain the sump but only about 2L from there... Plug was dirty but not gross.

Will let you know how I go...

 

You should be able to find something comparable. It is a proper cleaner, not a stop leak or any kind of other goo.

 

Wow,,, I'm working on a '92 Accord EX with virtually the same thing. Start and shift to any fwd gear, the trans engages. Go to "N", "R", or "P" and then go back to any fwd gear and no engagement. "R" will dwell, but eventually engages. No matter what I do though, combinations, revs, nothing, no engagement in a fwd gear. Shut the motor off, restart, go to a fwd gear and it will engage again. I've even brake-torqued it to the point of almost stalling and it stays engaged.

The driving test,,, start, "D3or4" and it is tight in 1st gear, shifts 2-3-4, but once you stop, no 1st gear, acts like it's in "N". Once again, shutoff, restart,fwd gear and it's very engaged.

I did Mad Mike's flush with some creativity. I drained, Fluid was nasty, plug mag was a slug ball. I filled the case with mineral spirits, did not start of course, and let soak overnight. Drained the next day. It was like dirty oil. Put a couple qts of ATF, swished and drained. Cleaned out the cooler and lines. Put in a pint of Seafoam and filled with ATF. Nothing changed, same problem. Drove a few miles in "1" and also let shift through gears, but same as before, once it shifts it won't go back to 1st. Acts like it's in "N". Shut off, restart, goes right into 1st. Let soak overnight, repeated the next day, no change.

For the third flush, I disconnected the cooler line and ran it into a funnel back into the case fill so I could see the pump/cooler pressure. Fluid flow is good for about 30 seconds and then tailers off to a trickle. Shift to any gear and the flow stops immediately,,, back to "N" or "P" and it doesn't recover. Once again, shutoff, restart, and flow is back to good.

I'd like to check the line pressure, but my trans pressure kit doesn't have a fitting for the line pressure plug,,, it's a course thread metric and I can't find a fitting to connect the gage to for checking line pressure. If anyone knows where to get one??

Unless Mad Mike or anyone else has any ideas, it looks like I'm pulling this thing and going inside to clean out the strainer and valve body.

 

Breaking down the mess, good good

Although I have no idea what mineral spirits may do to seals, I would not advise doing that. Now filling the trans with Trans Tune may be a better solution, if you can find it for cheap and in a gallon container...
What did the fluid look like after draining?
Have you checked out the TechAuto link? http://techauto.awardspace.com/transmission.html
Have you tested the shift solenoids, have you made sure the filter screens/valves are clean?
Have you checked the fluid level after charging every gear circuit?

I was able to find a fitting at the local ORLYs, had to go behind the counter to their 'specialty' cart with all the brass fittings. Forget what size it was, just bring the modulator test plug that is screwed in next to the A/B solenoids base for thread comparison. Fairly sure it was 6mm size but forget what the pitch was.

 

I didn't pump the mineral spirits through the system. Just let it sit in the case overnight to soften or "cut" any slurry that might be in the strainer. It looked like old engine oil when I drained it out, so the inside was at least some sludgy.
The second flush fluid came out red, but no longer see-through. It had obvious clutch dust like any old ATF does on a drain. The third flush was the same.
I did use an entire pint of Trans Tune on each flush and ran it all through the system each time. Drove at least a couple miles and did all kinds of shifting for an hour, maybe two with each flush,,, I really don't want to take this thing out.
The AB solenoid checked OK with volts and ohms. Good loud clicks with volts. I replaced it anyway. AB & CD solenoid screens were all clear with no sludge and no metal.
We also did your fill-level checks with all of the cycles. I even intentionally over-filled some on the third flush just to see if the system was cavitating somehow.
The thing bothering me is when I pulled the cooler outlet line and ran it into a funnel back into the case. It would putout good flow for 3-4 minutes and then drop to a trickle, then stop. The case level was still full and a little above the level top mark, so it seems like there's enough case fluid.
I'm headed out to find a fitting for the line pressure port and see if the pumps dead or on the way to being dead.
I really appreciate the TechArticle too. Great info. Thanks for the input too. It has all made sense, but the transmission doesn't want to cooperate. Trying to decide how much more to flush and clean before jerking it out.
Is there anything else you can think of??

 

Other than the Minmeral spirits - flush.... ???

I am at the same stage... After a few mins the flow stops and what does come through is rather frothy, not unlike air re: cavitation some where.

Can only assume the internal filter/s are blocked.

Shift and lock solenoids are good and have tested fully outside the car and even applied a flow to ensure they are not just activating but there is no crap in the seats and or if they are not seating correctly = ALL LOOKS GOOD.

 

Try letting it soak in mineral spirits again?
Did the time between when it stopped working before the mineral spirit soak and after the soak increase operational time? If so then I would think you are making progress. Might try reusing the mineral spirits if you can filter or let the gunk settle and then siphon the clean stuff off the top.

If you do plan on flushing/soaking again while the trans is draining, bypass the shifter interlock and select each gear. This may drain out some more fluid from the different gear circuits, might see if that helps drain out more junk as well.

This is what I believe is happening. How to clean the ports without having to pull the transmission, remove the case and pull the filter, would be nice to find out, but I think this may be the only proper way to fix such a problem.