Torque Converter in and out of Lockup

[Goodview]

Originally Posted by Hesperus

Have noticed the lack of the tranny making up it's mind as well on my 2010-figured it was the pathetic lack of torque around 1800-2000 rpm (around 45-50 mph), but seeing other posts, I wonder if it lies in the Transmission ECM software/version???
Don't know what any techs out there can tell us, but would think the 'brains' of the transmission are responsible for shift and lockup in the unit-instead of just flushing which is ok on high mileage, but should not be a problem unless there is an underlying Honda tranny issue which has happened in the past in their car lines.

Exactly. Older vehicles often have exhausted fluids or worn-out thermostats (or sensors) which need to be solved in order for the system to work as designed, but really, it's ultimately the 'brains' that decides where the shift points should be.

There's software upgrades for some problems, and there's always the 'idle learn procedure' for those who have tried the other fixes and still aren't happy with their tranny's personality.

You would never in a million years hear a Honda engineer say: 'get used to it'. Honda engineers aren't idiots. Their product can be made to work almost perfectly, despite the complacency of dealers and other bad advice that's floating around in the ether.

[wrp5a]

I apologize that this reply may be a bit 'out of order', but I too have fallen victim to this 'pulsing' at 45 mph, for the last 40k miles or so. I have and '06 with 120k miles on my rig, and I thought that changing the tranny fluid (the full 3x method) might alleviate the problem, but as other members have indicated, IT DIDN'T. Prior to the 'full' change, I had been doing the '3 quart' routine every 30 - 40K.

I have thoroughly read the only Transmission TSB, and I have not had any of those symptoms.

Has anyone pondered testing/replacing the fluid pressure sensors on the transmission? It appears that there are at least 2 of them, but I can't yet figure out which one would (might?) control the torque converter lockup. There is also a 'lockup solenoid' on the transmission which could be a culprit. I am trying to find out more information about how these components work. For $35/each, I can't see it being a bad gamble to replace the sensors.....the lockup solenoid would sting a bit more, but it's still better than replacing the tranny. I just can't convince myself that the internal workings could be shot at 120k....I want to sway more toward a bad sensor, or something along that line......but what do I know......

Here is a link to what I am talking about - not sure if it will show up right...might have to do a 'cut & paste'

http://parts.sonshonda.com/showAssem...rimLevel=15783

[IanRTL]

I'd be very interested in learning how to correct this problem. I'm still experiencing this issue periodically. Changing the transfer case and tranny fluid didn't help much, if any. I noticed it shortly after I bought my truck at 75k miles. The total changeover to DW-1 made it all but go away for awhile, but it returned. I'm now at 125k miles and it's just plain annoying. A pressure solenoid would make sense, but I just can't justify replacing a $200+ part without knowing if it works. I also haven't had any other need to go into the dealership, so I haven't had the tranny TSB done either. Truly a frustrating thing...

[StayPuff]

Originally Posted by cyclemax

No, there's definitely an issue. Fairly certain it's not hunting between 4 and 5 based on the minimal change in RPM. Downshifting to 4 creates significantly higher rpm. Slight hills and additional load actually alleviate the problem. And yes, nearing 50mph makes the condition go away.

Could be a "glitch" as one member suggested, but certainly shouldn't operate that way. I'll try to capture it in a video to post.

If I had to hypothesize, I'd say it's happening right at the cusp of certain conditions, one programmed for lockout and the other not. For example, at 45 under light load the ECM may lockout the TQ, but that change alone affects engine load, so it immediately unlocks, and the cycle repeats every second, causing the pulse.

FYI, if you lift your foot off the throttle the torque converter will unlock to allow for coasting.

You can replicate this at any speed on the highway; Keep your foot into it until you know it's locked in 5th under load, lift off to coast , reapply slight pressure to the throttle and watch your RPMs blip for 3-4 seconds until the lock re-engages.

The conditions that allow it to cruise at 45mph in 5th locked must be either flat or slightly downhill and therefore you are putting very light pressure on the throttle. Perhaps the highly acclaimed "Idle Learn Procedure" will help it to relearn where no-throttle is and keep it from thinking 'Hey I'm coasting'.

[dustboy]

I've definitely had this problem, in a couple different forms.

Sometimes the TC seems to hunt--the RPMs will go up and down ever so slightly about each second or so.

Then there is the vibration, which feels more like the TC is half-locked, like when my wife's manual Subaru had the dreaded "cold clutch shudder". Although on the Ridge it's much more subtle.

Either way, I've learned to avoid it. The vibration hasn't happened for several months, and I think it's because I subconsciously goose it into 4th when I feel like it's about to start.

[Rockwood]

Common problem experienced by Pilot and MDX and TL owners as well.
There is a TSB covering a reprogramming of the tranny and reported on the MDX site. Presume its available on RL to.
On the family Pilot replacing third and fourth gear pressure switches solved the issue. For 30k. I had been doing 30k fluid changes up until recently. When it came back just shy of 150k, another drain and refill using redline d ATF rather than Honda solved the problem.
So now I'm going to run 15k fluid changes on all my Hondas.


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[Jack]

Been a while since I posted to this thread. I now have 80k on my 08 and it still does the same, has not gotten worse or better. It's just the nature of the vehicle, poor thought out in some areas, light years ahead in many others.

And no, Ian, my next truck will be another Toyota. I traded my 4 door Taco in on the Ridge. Never had these issues with the Taco. I'm justsaying.

[IanRTL]

Oh I wouldn't blame you, Jack. Unfortunately it seems that you've had more issues than most with your ridge. Going back to something that never gave you any trouble would be something to do naturally. Have to be happy with what you're driving.


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[itasor]

My RL has this exact issue too. Unfortunately a lot of the driving around here is at 45mph. This is definitely just a RL thing? No sense having the dealer look at it if it is, would be a hassle to try to get covered under my extended warranty if there ends up being no fix.

[Jack]

I was wondereing if anyone knew how Honda tests these vehicles. It seemd that a lot of my driving is around 45 due to the traffic issues in the DC area, and mine pulses. It also seems to have some kind of CVT (constantly variable transmission) thing going on. When it downshifts going up a hill, when I crest the hill I get a high to low sounding RPM from the engine and the tach shows an rpm change that coincides with the sound. Sounds like its slipping/torque converter not locking up.


Ian, I had issues with my Taco as well, it just seems that I had less with the Taco than the Ridge. Anyway mines paid for so I'm going to drive it till it just dies.