2001 Accord EX V6 Sedan with 176k

I've had a couple things happen recently that might be related, might be unrelated, might be a transmission rebuild in the making, might be something less painful. I'm going to throw everything out there that I have read/suspect/noticed/etc. If there's too much information, my apologies.

I live in New England which may or may not be important.

Over the winter I had a couple minor issues that I wrote off as New England weather related problems (I've only lived up here a few years). A few times over the winter I had a few stutters off of dead stops. The TCS with flash and it would feel like I'd lost traction, then I'd grab and go. No problems otherwise. This happened once in a while so I just figured it was the enormous piles of sand that are all over intersections. The problem largely abated when spring came so I didn't really think much of it. I swapped my summer tires onto my car a few weeks ago and I have only had one TCS flashing moment similar to those winter ones that I can think of since.

Thursday night I was driving down to my father's about 250mi away. I got about an hour into the drive when my TCS and MIL popped on simultaneously. I happened to come up on a rest stop so I pulled in to take a quick look at everything. I shut the engine off. Turned it back on. TCS stayed off. MIL stayed on. Understandable. I checked fluids. ATF, dirty, but sufficient and not burnt. Oil, the same. I found I was a bit low on Coolant(not dry, but lower than the line), so I drove to the next exit, grabbed a bottle of premix and added some. I got back on the road and continued on my way. TCS came back on. I pull off the highway again, shut the car off. Turn it on. TCS stays off again. I resume driving, TCS comes back on. Okay. No TCS. I can live with that for a while. Weather is fair. Tires are good. I'm not stupid. I'll fix this later. I drive another hour or so and stop for dinner. Car is off for a good 30minutes. At this point, I took dinner as an opportunity to put my phone to use and start checking the Internet for possible causes of TCS and MIL together. I come across an Yahoo question discussing possible EGR problems here. That is comforting and something that seems fairly repairable. However, my stock in Yahoo Answers is low so I'm not sold.

When I turn it on, TCS is off. TCS remains off for the rest of the drive (About 2.5 hours). I get to my father's house where I've conveniently bought him an OBDII reader last Christmas. I pull the code. P0740. Torque Converter Clutch Circuit Malfunction. That's bad. However, I note that there's a few possible causes other than the converter failing directly. The site I found the DTC translation lists off Solenoid problems, electrical or the Transmission Control Module as possible causes.

I search a few more sites, find some old threads on some boards and have determined it could also be, low or dirty ATF, a sensor (one of the pressure sensors? I'm not sure which the thread I found that mentioned that was referring to).

I clear the code and go to bed unhappy. In the morning I decide that while I have things to do in the afternoon, I can try something in the morning. The 2001 Owner's manual lists ATF for the AT being done at 120k(or 72mo) and then every 90k(or 60mo). It's been about 60mo since I did mine, I was planning on doing ATF at the end of the summer. Can't hurt to do a pan's worth now. I drive off to Honda to get some ATF as I recall the world being very adamant about not using anything but Honda ATF when I did it last time. I get a couple rough shifts on the way to Honda. This is about a 30min drive with speeds varying from 25-65mph. There are traffic lights and hills. The shifts are slightly rougher going uphill, low gears, low RPM. I get a pan's worth of ATF and head home. On the way home the shifts are noticably rougher than they were on the way to Honda. 1-2, 2-3 and 3-4 are all ugly. Not always, but frequently enough that I'm trying to baby the car down the highway, trying to maintain speed and not shift as much as I can. A couple of the shifts are clear over revs.

I drain the pan and put in 3 QTs. the nose of the car was up in the air so that there wasn't room for the 0.2 out of the 4th qt I bought. That being the reason only dawns on me hours after when I remember that the last time that I changed it, I had put the back end on jack stands higher than the front ones because of the plug location. Volume on the stick is on the high side of acceptable. Just about the high dot. I start the car up and go for a spin. The car feels fine. Upshifts are fine. Downshifts are fine. I take the car on the highway and punch it to 60 off a couple lights. No problem. I head down a few back roads, deliberately stopping and accelerating again to force the car to shift. I even stop on a few step inclines where I'd had problems over the winter. Everything is great. Content with my work, I leave my father's to take care of the business I had to on Friday afternoon.

That took me into NYC, about an hour and change drive. As I got onto the city streets, I got a few rough shifts. These weren't egregiously rough, but noticeable slips. I park the car for a couple hours while I attend to the purpose of my trip. I get back in and proceed to drive back home to New England. I drive streets, the BQE, the FDR, Buckner, CCE, and everything else. Traffic was stop and go since I left in rush hour. I stop for dinner in about 2 hours after I started, successfully having made it to CT. There was virtually no slipping while leaving NYC. The car sits for about 30minutes before I'm back on the road. About 150Mi after leaving my father's that morning, the TCS and MIL come back on simultaneously. I pull over, power off and on the car. TCS stays off. I drive the remaining hundred miles home uneventfully. There's virtually no slipping.

My fiance and I had things to do this weekend so we took her car and I got to take mine out again this morning to go to work. Drive is about 30min, 25-65mph roads. Thought I might have felt a slip at the very end but it was so minor I can't be sure I wasn't imagining it. I took the scenic route home 45 min with about the same speeds. No slipping.

This leaves me with a couple questions:
So where do I start? I have some money saved away but the budget isn't limitless so I don't want to resign myself to a rebuild if a rebuild isn't necessary. (A new car is way out of my price range right now. Even a rebuild is pretty much draining the bank account)

1. Change more ATF. (Maybe I was a touch too high and the hot engine of prolonged driving was unhappy about expansion?)

2. Change/clean the EGR?

3. Change/Clean the TCC Solenoid (I saw someone who just opening and cleaning teh assembly did wonders for)

4. Change sensor(Speed Sensor I presume?)

5. Check all the transmission wiring for a loose connection and spend a day with a multimeter.

6. Do I need more data? I have only tried these in D4. The problem isn't constant, but I can try spending a day driving around in D3 to see if that hiccups. I could also do a bunch of starts off 2 and 1 if those could help diagnose.

7. I noticed that Honda switched from Z1 to DW1. I did some reading and some folks suggested switching to Valvoline Max Life because it was more similar to Z1 than DW1 is. Anyone have any good experiences with it? Bad experiences with it? if I can solve this problem, I'm thinking I might need to change the ATF more frequently than the Owner's Manual suggests and the Maxlife is significantly cheaper than DW1.


I have the maintenance books so, I can go through those if you happen to know what section I need to look at, then I'll decide if its a solo, get a more experienced buddy or shop job.

Thanks a lot for your help in advance.

 

Here is a thread talking about P0740:

https://www.hondaaccordforum.com/for...options-41003/

 

Thanks. I didn't think to search by the DTC here. My brain must be cooked as that should have been obvious and googling just got me generic stuff.

Happily, I was thinking the solenoid(Why else would it not appear until significant highway driving). Come to think of it. One thing I forgot to say is that when I used to do a full tank highway, I'd get 27mpg or so but I've been down to 25mpg lately. I'd written it off as just age since one upon a time I got 30mpg on occasion.

Since I don't want to raise that thread from the dead. Given that unlike that post, I did not drive over a curb, would you suggest starting with a good cleaning? Do you have a recommended cleaning method? Dawn and water? Just water? air compressor? I've never taken any part of any transmission apart so I don't want to do anything to monumentally stupid. This would specifically be the lockup solenoid that I'm seeing on parts listings, correct? I'm seeing it for about $300. Or should I hit the shift solenoids as well?

Do you think the slipping I was feeling was related to that or simply a case of aged fluid on top of a bad solenoid?

Thanks again! You've made my night be pretty much telling me I'm not having my whole transmission rebuilt.

 

Transmissions are the most complicated part of your car. This may still be caused by clogged fluid passages throughout the transmission, aka a bad transmission. The 98-02 V6 accords have high rates of transmission failures compared to other generations of accords.

When you remove the solenoid, there is a screen that may be clogged. See video below. I would wipe out the outside of that screen. Then I'd spray with throttle body cleaner to get any material out of both the solenoids. I would not attempt to disassemble the solenoid, and I am not sure this is possible.

Check your fluid level and adjust if necessary. The engine has to be hot and turned off to check the fluid level (please verify in your owner's manual).