Variable Cylinder Management

[sak22]

I recently purchased a brand new 2009 Odyssey with Variable Cylinder Management (VCM) that essentially cuts of 2 or 3 cylinders during cruising mode (depending on throttle response) and back up to 6 cylinders under load... All this for better fuel economy. I have read the literature and my owners manual from cover to cover and it states that this process is seemless while driving and you don't feel it working. Well I can tell you that both my wife and I feel it nearly every time we get behind the wheel. It comes in the form of a clunking or thumping and sometimes with a hesitation. We feel it mostly with stop and go city driving, but also on the open highway when we go up or down a grade. My question to those that also have this technology in their engines is simple: Is this normal or is it REALLY suppose to be seemless. I have read that it is suppose to be seemless, but have also read that it's normal?! One suggestion was to take it to the dealer and have the PCM re-flashed to correct it? The van of course is under warranty and I will take it in if neccessary, just wanted to get your thoughts and opinions. Thanks.

[dgsbikes]

Seamless beyond the sometimes noticeable surge in power with switching from 3 to 6 cylinders firing.

But no noise, jerks, shudders or anything of that sort.

[ArtChee]

STRANGE.... I just bought a 2006 Odessey Touring model, and on our 600 mile trip back home had to watch the dash to see when the VCM changed. No noticable change in performance at all. Of course, I WAS disappointed in the only 23 mpg with this feature, which is SUPPOSED to get up to 28 mpg on the highway.

[Moppie]

Originally Posted by sak22

I recently purchased a brand new 2009 Odyssey with Variable Cylinder Management (VCM) that essentially cuts of 2 or 3 cylinders during cruising mode (depending on throttle response) and back up to 6 cylinders under load... All this for better fuel economy. I have read the literature and my owners manual from cover to cover and it states that this process is seemless while driving and you don't feel it working. Well I can tell you that both my wife and I feel it nearly every time we get behind the wheel. It comes in the form of a clunking or thumping and sometimes with a hesitation. We feel it mostly with stop and go city driving, but also on the open highway when we go up or down a grade. My question to those that also have this technology in their engines is simple: Is this normal or is it REALLY suppose to be seemless. I have read that it is suppose to be seemless, but have also read that it's normal?! One suggestion was to take it to the dealer and have the PCM re-flashed to correct it? The van of course is under warranty and I will take it in if neccessary, just wanted to get your thoughts and opinions. Thanks.

It might be worth getting it looked at, if it's under warranty you have nothing to loose

Honda builds some of the worlds best engines, they have been described as one of the worlds top 3, along with Ferrari and BMW and are very experienced at building engines with smooth transitions between different power modes.

Originally Posted by ArtChee

STRANGE.... I just bought a 2006 Odessey Touring model, and on our 600 mile trip back home had to watch the dash to see when the VCM changed. No noticable change in performance at all. Of course, I WAS disappointed in the only 23 mpg with this feature, which is SUPPOSED to get up to 28 mpg on the highway.

23 is pretty low, were hauling a lot of weight?

[ArtChee]

Originally Posted by Moppie

23 is pretty low, were hauling a lot of weight?

No particular load. No passengers. Maybe only a couple hundred pounds of luggage load.

[BullShifter]

Does it have bad engine mounts? I can't tell you how many I've replaced lately on Honda's, especially Odyssey's. It really sucks for the customer when it has VCM. Those mounts are $600 a piece just for the part from Honda. I've had to do the front and back back on a touring model. It's easy to tell if the mounts are bad. With the car in drive hold the brakes hard and hit the gas a little(quickly), do this in drive and reverse. If you hear a clunk, or feel a bang chances are one of the mounts is bad. Someone watching the engine can usually tell which end is moving more.

[ArtChee]

Originally Posted by BullShifter

Does it have bad engine mounts? I can't tell you how many I've replaced lately on Honda's, especially Odyssey's. It really sucks for the customer when it has VCM. Those mounts are $600 a piece just for the part from Honda. I've had to do the front and back back on a touring model. It's easy to tell if the mounts are bad. With the car in drive hold the brakes hard and hit the gas a little(quickly), do this in drive and reverse. If you hear a clunk, or feel a bang chances are one of the mounts is bad. Someone watching the engine can usually tell which end is moving more.

Engine Mounts???? Wow. Will check into this. If a motor mount would correct this, would need to drive over a thousand miles to get money back.

[sak22]

Checked out fine at the Honda dealer... Two different Honda dealers. They say absolutely nothing wrong and motor mounts look fine. I ran the suggested tests with no clunking or banging... all is nice and smooth.