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To shift or Not to Shift?

I have an '08 Accord Cpe with a V6 and 5 speed auto. transmission. When driving on a level stretch of road trying to hold the speed at 40mph the engine speed will bounce up and down between 1400 and 1700 RPM. The engine is warm. The transmission feels like it is trying to up-shift and make the car go faster thus nearly impossible to hold the speed at 40mph. If I put the transmission in 3rd gear so it can’t shift up there isn’t this problem. I have also noticed a lugging or hesitating when trying to accelerate when the engine is cold. I wonder if these are related issues ? Any ideas ?

Sounds like the car is hunting between gears. I would put the car in cruise control at 40 mph and see if it can effortlessly maintain that speed. If it can, then in those conditions, I would down shift to minimize the hunting.
If being a 6 cylinder, it can’t maintain a steady speed with the cruise at 40 mph, it may need a mechanic’s attention.

Disagree. Automatic means automatic. Only downshift on a very long, steep downhill to avoid brakes from overheating. Is there a toggle switch to turn off the overdrive? Use that.

However, neither way will do any damage. Do what makes you happy.

dagosa could be right…I’ve seen vehicles that were grossly underpowered (like the GMC Jimmy and the 2.8l V6). That vehicle would burn out automatics quickly. Constantly up-shifting and down-shifting. When GM upgraded to the much more powerful 4.3l (keeping the same automatic)…the tranny’s were no longer burning out.

But a V6 Accord is grossly OVERpowered.

Don’t know if it is or not. Could also NOT be running right…

Has it always done this? The description suggests a torque converter clutch that is dropping in and out of lock up. This can happen for multiple reasons.

If Americans demand a V-6, Honda will sell them one (but not a V-8, they have to draw the line somewhere). BMW, Mercedes and Porsche will sell the American public an SUV. The German engineers must cringe and ask for psychiatric counseling when asked to design an SUV. (Excuse me while I go to the bathroom to take care of business.)

I have a Honda Accord 4-cyl, and power is perfectly adequate. It gets better gas mileage than a 6 and is a whole, whole lot easier to work on.

I apologize for adding a comment in my original post after others had replied, but, in my experience, like"mleich" the v6 Honda is plenty powerful enough, though at higher rpms like Hondas in general. My manual recommends and I have done it in the past, shifting to lower gears at some speeds to avoid hunting. Did this with v6 Toyotas which had equally powerful motors. I believe using the cruise control test might take out some variability introduced by the driver subconciously.

And, mleich…we really don’t disagree when you say, “disengage the OD” and I say downshift. OD is just another gear for all practical purposes.

Secondly, like"cig"; has there been a change in performance or has this been happening since the car was new. Nothing like a test drive of a similar model to bring out faults in a car.

I drive Accords at work, and I don’t believe the OP’s car is acting normally. The shifting and transitions should be seemless and not noticable.

If the car has not been otherwise checked out and verified to be operating properly, it shoud be. Poor engine operation, insufficient power, can caiuse this form of hunting.

If the engine has been checked out and verified to be operating properly, the tranny needs to be looked at.

Bottom line: IMHO this is not normal and should be diagnosed.

How many miles on the car? Scheduled maintenance up to date?
Check engine light on? Get the error code read.
Check trans fluid level and appearance. Drain and refill with Honda fluid if older than 30k miles.
Does this engine have an MAF sensor? Clean it.

I wouldn’t call a V6 Accord grossly overpowered. It’s peppy, and certainly it’s not underpowered, but it’s not like it’s packing an alcohol burning Boss 9 under the hood. The I4 powered Accords are adequate in my estimation, they have just enough power so that you don’t complain about it.

If you solve your lugging/hesitation problem the shifting problem will probably be solved.

I do not think there are related issues, but if it were my car would use the option to lock in a gear at a reasonable rpm and skip the up and down shifting. Better gas mileage idea gone bad.

thank you all for your comments.

Does it stay in gear at 35 or 45 MPH? At 1400 RPMs, it seems like it is ready to downshift. I have a V6 Accord and do not have the same issue, but Where the speed limit is 40 is a flat stretch of road. Experiment a little with your speed and see if gear hunting disappears at slightly higher or lower speeds. I cruise around 1800 RPM at 55 MPH in 5th, so this might be normal.

My V6 Accord’s power is more than adequate, especially at low speeds. That’s one of the reasons I bought it. As FoDaddy says, it’s not breathtaking. But power is very good for anything I encounter in daily driving. The gas mileage is good, too. I get 28 MPG commuting.