on the freeway, my accord feels like it is downshifting from lockup to 4th gear. The tach goes up about 300 rpm's for a few seconds and then back down to where they were. one shop wants to rebuild the tranny and another says they couldn't get it to do what I said it was doing. Any suggestions? Thanks, John

 

Could be a failing solenoid, but that would usually set a code. Does your D4 light work? Check for stored codes in the ECU. Blue two wire connector hidden over the passenger side kick panel, turn the car to ON and read the code(s) from the CEL or D4 light.

If there are no codes, you may need to pull the solenoids apart and clean the pintle valve and screen. If a valve is clogged or allowing a bleed down of pressure it could simply be the fluid pressure drops, then picks back up and bleeds down again.
http://techauto.awardspace.com/transmission.html

 

The D4 and S lights are not blinking. There are no codes from the blue connector. If I remove the solenoid, is there fluid pressure behind it? Will it make a mess? I have seen how to check it on youtube. Can I just put it back on? Thank you for your reply, John

 

There will be a small amount of fluid that will drip out when they are removed. I personally would just put a thin coat of silicone on the old o-rings just to be sure they don't leak.

You should also check the throttle control cable - runs from the tb to the trans - to be sure it has the proper adjustment/movement.

Last, when was the last time the fluid was changed in the trans?

 

Any luck with this? after a 2nd drive in my car...this is exactly what is happening to me as well....it's going up by about 500rpms....then back down....anywhere between 50-70mph....it is def not downshifting into 3rd because when I do that manually it..it revs much higher than that.

Any luck with cleaning the solenoids? I do change my tranny oil yearly.
Do you think new solenoids are a good cure?

 

Check your thermostat. It could be malfunctioning and not getting the car to operating temperature. I had the same problem and it turned out the thermostat was bad (leaking seal). After it was replaced, lockup works.

 

 

OK everybody...by looking on youtube and on other tech forums I think I fixed the problem. I disconnected the single wire on the left side of the engine and sprayed it with some maf sensor cleaner I had. I think it is the wire that goes to the temp gauge. I also unplugged the connector behind the single wire and cleaned it. Then I located the fast idle valve (look on youtube) I unscrewed the two Phillips screws from the top and used a flat screwdriver to turn the round thing inside down until it bottomed out. (not real tight) The car has been running fine since then. Thanks to all people that post things on the internet.

 

I didn't mess with the solenoids. I only cleaned those two connectors and screwed in that other thing.

 

Did that really fix your problem? doesn't sound right but im going to try and find the first wire that you mean i guess and give it a try. Hope you don't mean air tubing.

 

There are four thermoresistor sensors. If there is a bad connection the ECU may not know the correct temp and not command lockup.


When the engine is cold, 4th will not engage below~45MPH.
When the engine is warm 4th can be engaged below 30MPH at a steady cruise.
It's always a good idea to check that the car is reaching full temp, the thermostat is working properly, and that the sensors are within spec with good electical connections and that the sensors are not coated in goo or gunk from old antifreeze buildup, scale or stop leak gunk.

 

there are pictures posted on another forum: Honda Accord forum...do a search for: auto tranny lockup intermittent...you will have a choice of replies...click on threads...scroll down to the pictures...the guy is pointing to the single wire connection...on youtube look up Honda idle problems...The best video I found is from Eric the car guy. He seems to know what he is talking about.

 

Wanted to follow up...unbeleivably this seems to have cleared up the problem!!

I did a combo of things because they were cheap enough and well at over 20 yrs old....why not? I replaced the thermostat and it was an older kind with a rubber insider that had broken up some...not the outer rubber seal an inner seal where as the new one seal flush metal on metal.

I then went on to clean out idle control valve and it was dirty.
I also did the fast idle valve as it was simple enough.

Then I went to clean the connector on the side of the head and it gave me a hard time to remove...in the process it broke...snapped right off. I beleive it was toasted and brittle. Ran to the store and bought another one...I think it was 12 bux. To my surprise it was no hard time to remove from the head...but the part that got stuck inside the connector would still not come out....eventually i ended up having to basically drill it out carefully without damaging the connector.

End results were good...its been a few weeks and the problem has not returned...knock on wood. Thanks again!