My '07 Ridgeline RTL with 136k miles has lost power/not shifting. On any uphill climb, I can't get past 22 mph until the pedal gets 100% fully depressed to the floor, after a few seconds it finally downshifts and I'm near 5k rpms. I can work the throttle to upshift, get rpms down closer to 4,200k and slowly build speed. I can be at a high speed, such as 50 mph, head into an incline and the speed just drops like I don't even have the throttle open or I can be at a stop and have to gain speed in 1st with it just rapping out rpms and it will only upshift if I work the throttle. It's difficult to describe how I have to work the throttle to downshift but close to feathering.

I also experience this with the need to rapidly accelerate. Again, I can't get it to downshift to pass someone without full pedal to the floor.

It's sluggish on regular takeoffs but much less disturbing than trying to pass someone and there's nothing extra to get me around a car or decelerating quickly with cars behind me.

I've always kept it well maintained with fluid changes, air filter, plugs, etc. I just replaced the plugs in hopes it would help. Nothing changed.

I haven't done a compression test yet.

Any suggestions?

 

A few other items... I run a can of Seafoam about every 9 months. I haven't recently.

I've read a number of other threads and there's a common comment about Honda's quirky downshifting but this is a different performance than the last 9 years.

One recent change is a move to higher elevation, 7,000'.

The next thing on the list is resetting and re-learning the ILP and CKP. It feels like its related to shifting. I'll notice at times I'm on a 45 mph stretch after a stop and I'll be maintaining speed at 45 and still at 4k rpms and I have to feather the throttle to get the downshift.

 

It's gotta be throwing a code, even if it's not throwing the light.

 

I've read seafoam can clog catalytic converters. Does exhaust seem to be flowing well from your tail pipe at idle? I doubt your's is in issue but it's one thing that is easy to check by just putting your hand next to the tail pipe when idling.

When you say fluid changes, have you regularly done the 3 x 3 drain and fills on the transmission? It sounds to me like the valve bodies are clogging up as well as the torque converter. Not sure if Honda ever did ad an inline filter to their automatic systems.

 

Thanks for the info. I have always done the triple D&F. Any recommendation on cleaning up the valve bodies?

 

To be honest, the only valve bodies I did any research on wasn't even Honda. Also, that's purely a guess on my part as that is what it sort of sounds like clogged up valve bodies. I suspect there are other systems that could cause similar behavior. Also clogged valve bodies would also point to worn clutch packs to go along with all the clogged up parts.

Checking helminc.com, they do offer the factory service manual for the 2006-2008 Ridgeline. They are out of stock at the moment, but it is available which is good for you.

With that, you will be able to go through and trouble shoot your transmission. The only Honda Automatic I have any reference material for is the 92-00 civic automatics.

I don't even know if the solenoids stuck around on Honda automatics after 2000. I do believe the Transmission Control Modules became even more elaborate.

Best of luck.