Honda Accord VCM
Just picked up my new 08 Accord EXL-V6 with Navi etc Sat. This is my 6th Accord. Ok so I get the whole "gogreenloweremissionssavefuel gig". But here is what noone is talking about yet and so far, I appear to be the first..... VCM (Variable Cylinder Management) Hondas new generation engine for the Accord is different then engine they have been using in the Odyssey. Ya see in the Van version Honda implemented a 6 cylinder to 3 cylinder VCM function. in the 08 Accords its 6-4-3. The issue is this... when you are in the city you will rarely notice anything, maybe when the "ECO" light comes on you may feel a slight hesitation a 1/2 second after but, overall with all the stopping and starting etc you cant seem to notice anything out of the ordinary. Ok so here is the rub,,, take it out on the highway and run the car at about 65-70 miles per hour (normal within the speed limit) cruising and you will begin to feel the VCM system trying to figure out what it wants to be when it grows up... you "may" feel the car surging and slight hints of hesitation as it jumps from 6-4-3 cylinders.. those of you that like to feel the road and are "in tune" with your ride "may" just get frustrated. Add on top of that the new "Grade-Logic" system and what you end up with is a a car that can (at times), feel like its trying to get into gear (at least mine anyway). This seems to be minimized when in "cruise control". I found this hesitation and/or surging felling no matter how stable I kept my foot on the gas, even going so far as to lock my ankle in one position thinking the gas pedal may just be super sensitive. I took it into the dealer today and they ran about every computer test they had on it and all was ok (or at least within specs). in fact we road tested two other V6's and sure enough... same drill. So caveat emptor (buyer beware) the car is awesome in almost every respect BUT just be sure that you know what you're buying and how it operates. It is different than your run of the mill V6 engine. Yes its a new technology and yes I drove a standard V6 for years, so I need to get used to this, and (of course) I am sure I will, ( well a pray I will after dropping $30K)... but if you are concerned that yours is having issues or that it is not running correctly... it most likely is (as designed). My salesman had me believe that the only thing you I would notice is the "ECO" light coming on and that just isn't the case in my experience.
0
Comments
I too own an 08 EXL V6 non nav model. Now have about 3,800 miles on it, including an 1,800 mile highway trip.
Unlike the above users, I do not find the cylinder change objectionable. I do agree that you can "feel" it, especially if you are watching the "ecomomy" light. What I experienced, however, on the highway was I thought a rather pleasant addition of power when going up grades. On cruise control, I noted that as grades were encountered, it switched to 6 cylinder operation with a slight increase in power, much like a downshift.
A side benefit is that unless the grade is pretty steep, the transmission DOES NOT downshift as with most cars. (You can observe this by the rock steady RPM). The engine does run at relatively high RPM vs other V6's (my 07 Toyota RAV4 for instance), but probably due to this higher RPM and the ability to engage more cylinders, it does very little shifting at speed limits.
On one of the non-Edmunds 2008 Accord forums, several posters have become alarmed because a few almost new 2008 EX-L V-6's with 1000 miles or less have been immediately put up for sale by private owners. Nobody knows why... could be because of what you described.
I have yet to drive the 2008 EX-L V6. The car is on my list. I would insist on driving it on the interstate to see if I can duplicate what you describe. Coming from three BMW's, that would definitely bother me.
None of the reviews I have read indicate the VCM problem.
Disappointing.
Must be at least 10 reviews saying the same thing.
One reviewer called the VCM's operation "seamless."
This is the first time I have heard anything to the contrary.
On the other hand, there seems to be a consensus of unhappiness with the performance of the 5 speed automatic transmission.
With regard to the 5 speed auto tranny, I do not believe there is a "consensus of unhappiness" with its performance. It gets glowing reviews from the pros and gets a glowing review from me
Since you claimed this is your sixth Accord, I'm also curious why you said "grade logic" was new.
"The engines deserve better partners. When hooked up to either one, the still-five-speed automatics didn't behave well. They occasionally held a gear too long or refused to downshift or bumped when going from gear to gear."
There are other reviews where unhappiness with the 5 speed automatic is expressed:
Motor Trend in comparing the Camry SE to the Accord EX-V6 found that "Toyota's 6 speed automatic outclasses the Accord's 5-speed."
Cars.com wrote that "upshifts can be a little jerky at times."
US News and World Report: "Automotive writers are mostly dismayed with the Accord's 5-speed automatic transmission."
Nevertheless, I plan on driving a 2008 EX V-6 sedan. Like I said, this vehicle is on my shopping list.
I am more concerned about feeling the VCM than anything about the transmission.
I hope other owners of the V-6 sedan come forward and can enlighten us on their VCM experiences.
The Accord did, however, win that comparison. And while they did say they liked the Camry's 6 speed transmission better, would they have liked it so much if it started the flare-up issue, that has probably been at least part of why CR doesn't give the Camry V6 "reliable" status. Maybe Honda wants to make sure a 6 speed auto trans will be reliable, before putting it in the Accord. The 5 speed automatic in my 03 EX V6 has been flawless in it's operation. More speeds means more complexity, and more needless shifting, for the sake of acceleration and fuel mileage. Just my thoughts on the subject.
I do believe what dissatisfies many reviewers, most drivers probably don't even notice or care.
I really want to like this car. I am coming off lease in July and I have high hopes for the EX V6. (I should be able to swing sub-invoice by then!)
First off like I said in my 1st post on this issue, city driving you will hardly feel much of anything. This is due to lower speeds, less constant cruising speeds and the basic "stopping and starting" or braking and accelerating that we all find consistent with non-highway driving. In lower speeds its a bit less distinguishable due to simply put, more shifting.
On highway driving is where I found the VCM to be most noticiable. flat open road minimal road wear conditions(i.e check holes, asphalt repairs etc) In fact interstate 71 in Ohio. Between 65 and 70 mph and off Cruise Control. That is the funny thing,I dont notice the changes as much in the computer aided CC. Now, I know what you are going to say, perhaps I have a lead foot, cant tell that I am adding pressure to the gas pedal or pulling off. I too, felt that was a possibility so i tested this thing for a total of 4 hours. 2 hours up to my location and 2 hours back, locking my foot in place at times. I see no reduction in speed on the speedometer OR any real noticable, instrumental change in the RPM.
Hope that helps.
So, just be cautious, dont listen to the sales-guy... listen to your self when you test drive it, feel it and consider the purchase,, thats my story and I am sticking to it ;-) GolfrSki
There is an auto show coming to my town on Thursday so I will at least be able to sit in one without the usual pressure. I hope the seating adjustment is not disconnected.
The auto show is coming to my town (Birmingham, AL) on Thursday. Whereabouts are ya?
Replying to: seeker12 (Oct 08, 2007 12:11 pm)
I've been enjoying the EX-L V6 Sedan for a couple of weeks. Only have about 600 miles on it but I don't find the variable cylinder system to be that noticeable. Unlike most reviewers that say it’s completely unnoticeable I can feel a little more going on then just the transmission shifting. When you consider the frequency that the ECO light on the dash comes on, this system is constantly making adjustments based on the terrain and attitude your right foot has with the accelerator, and anything that is activated as often as this is, based on my driving style, Honda better have gotten it right or it could be a big headache for both Honda and myself. I previously drove a 2003 Taurus and I'm amazed at the size of the new Accord. With 4 adults conversing while traveling 70 MPH on an interstate the Eco light tells me I'm getting a reasonable return on a gallon of gas, no one is shouting as the cabin is quiet and when you look in the rear view mirror and see your rear passengers seemingly in another zip code I smile and feel I made the right choice and I've got a lot of car for what I paid.
This is one of my first post on any of the Accord Forums and I almost regret posting it. To not purchase this car because something that is mechanical in nature and can be barely noticed would be absurd. Would you change your mind on the purchase of an automobile because you could feel the tranny shifting? What can be felt cannot be considered a surge or a clunk or a shudder, as it is less noticeable then a shift. I know a lot of Honda drivers make their purchase on a multitude of considerations, it's legendary reliability, form and function of most switchgear etc. But many are also driving their Honda's because they enjoy driving and sometimes, actually frequently they get a little frisky with their car because you can, they are fun cars to drive. So I mentioned the VCM as a perceptible feature on the new 08's just as a heads up to those who have a history with Honda and enthusiast driving styles so that they may pay a little more attention during their test drive to see if it's something that they may find objectionable.
Last year I sat in many vehicles at the auto show and I must say the only one that satisfied me from a comfort standpoint was the Honda Coupe. The worst was the Lexus RX. (designed for someone not over 5'10").
I'm not interested in the navigation, so I don't think a lot of buttons would be a problem.
Sounds like the Accord EX-L V-6 with navigation is as complicated as the MDX tech.
I'm sure the Accord they display at the auto show will be the loaded EX-L V-6 with navigation.
I have a two year old 6M coupe that gets fantastic freeway mileage.
With this in mind, the VCM is of real interest. However, I am enamored of the smooth 6M transmission - - - - no VCM avail.
I would think - taching 2 grand or so in the automatics' high gear - using three cylinders - - - - some really impressive numbers are possible.
Please keep those cards and letters coming (joke)
Look forward to additional mpg reports (no joke)
all the best, ez...
..aye, aye, sir...
He knows what it means.
Thanks hpowders ;-)
I have been driving quite a bit around Tampa and have yet to see my first 2008 Accord Coupe or Sedan.
If this continues, sub-invoice deals can't be too far away.
Looking forward to my first glimpses at the auto show on Thursday.
I won't make the mistake of asking the gorgeous model in front of the Honda exhibit anything about VCM.
Like you, I sure would like to hear from other purchasers of the Accord EX V-6 Sedan concerning their experiences with VCM.
Noticeable or seamless?
In short, depending on how much power is required from the engine, it can run on all 6 cylinders, 4 cylinders, or 3. Thereby increasing fuel mileage.
Feedback from people who have lived with the vehicle for a while would be more revealing, IMO.
With the new Accord, Honda introduced second generation VCM. This version added yet another mode. Now, the engine is able to operate in 6 or 4 or 3 cylinder modes depending on need. This is also the new system in 2008 Odyssey. Pilot still has the old system, but with redesign that is about to happen, its 2WD version is likely to get this new system.
During idling, low speed/low engine load driving conditions, only 3-cylinders are producing power (all cylinders are "fired" but only three cylinder are being fed gasoline and air as the valves on other cylinders remain shut... the pistons still move in all of them). This is the "I-3" mode.
Accelerating from a stop, accelerating with moderate to heavy throttle and while climbing relatively steep hills, all six cylinders are fed gasoline and air, and fired. This is the V6 mode.
During moderate/high speed cruising, mild hills, only four cylinders provide power. This is the V4 mode (two cylinders from each bank are selected).
...no VCM is provided for the 6M.
VCM remains (at least to me) of real interest within the Honda sphere of fuel efficiency addressal. Keep those (VCM) cards and letters coming. I'm looking for a VCM six to break the 40 mpg barrier (after break-in of course)
..ah, the agony of choice!
..best, ez....