I have searched the owner's manual (pdf form), and can find no mention of VCM (or even the word 'variable'). My vehicle is a 2014 RDX w/Technology package.

Does it have VCM? I have seen no indication (no mention even of icons/lights, nor did I see a light come on when on a trip that on which I would expect VCM to activate if it is there?

If it is somehow optional, is there a way to determine if my vehicle has this function?

Thanks.


RFT!!!
Dave Kelsen
--
"More than any time in history, mankind now faces a crossroads. One path leads to despair and utter hopelessness, the other to total extinction. Let us pray that we have the wisdom to choose correctly." -- Woody Allen

 

Yes,it has VCM.You may notice a slight rumbling sound at about 29,39,49,59 mph,when driving on a flat stretch of road.Your mid display will show higher miles per gallon at that time.If You don't notice when VCM kicks in,You should not try to hear it.Because You will always hear it from that time. It becomes annoying to some people.

 

Thanks; I have done a bit more research, and I know that it is a part of the vehicle now. I now have to ponder if installing a VCM blocker would be staving off a potential problem, or if Honda has figured out a way to keep the oiling problems from happening.

I don't think the actual operation of the VCM will cause me any grief. I still wonder a bit why there is no mention of it at all in any of the manuals. Anyway, thanks again for the response.


RFT!!!
Dave Kelsen
--
Contra Felicem vix deus vires habet (Against a lucky man, a god scarcely has power).

 

Just a word of warning: I read several other reports of users who installed VCM primarily because of vibration. My RDX recently fouled a spark plug, causing an engine misfire, and has been burning oil since around 80k miles. Apparently VCM operation can have adverse affects on the vehicles piston rings. I'd recommend considering a VCM muzzler for the longevity of your engine as well.

 

I am an active member both here (wife's 2016 RDX) and at the Odyclub (my 2015 EX-L Odyssey) I can tell you that, in the RDX,
the VCM system is just about as good as it gets. It is slightly better in the post 2016 ones (6 to 3 cylinders instead of the 6 to 3 or 4 of the 2013-2015) you can hardly feel or hear it at all. I would still highly recommend using a "muzzler" anyway. Just because you can't feel or hear it, does not mean it is not fouling spark plugs and burning oil. There were specific Honda engines with low friction piston rings where these problems were almost assured, a lawsuit and warranty extension. However, over at the Odyclub there have been some case of newer vans, not covered by the warranty extension, exhibiting the same fouled plugs. It tends to take until about 70 to 80K before issue show up.

Here is the currently best Muzzler unit(s)

VCMTunerII Advanced

S-VCM

Both easily found with a Google search. Both automatically adjust themselves, can be configured to have a shut off switch.

The tuner one will shut shut itself off in an overheat situation and show the actual temp on the instrument cluster gauge. It also shuts itself off when the engine idles for a while, allowing diagnostics without removal. Both of these units do require a wire to the battery. The cheaper ones do not, but do require that you adjust them to meet your climate. Those may allow the VCM to operate occasionally. No big deal unless the temp swings where you live and travel are great. I'm in SoCal and have a simple one with a dial, left it at the default, and have had not VCM engagement since installing. (The Odyssey has an "eco" light that indicates VCM)

 

Thanks, egads. That sounds very similar to what I had figured myself. Although my 2014 already has 117K miles on it, the Tuner will likely be a good investment for me.


RFT!!!
Dave Kelsen
--
Friends help you move. Real friends help you move bodies.

 

My 2014 RDX has about 110,000 miles and no issues at all.

 

Does the use of a vcm muzzler decrease gas mileage?

 

Yes, it does. Anywhere from 1-3 mpg overall, depending on your use. (I haven't driven long with it, and haven't driven at all without it -- but I have read every thread on the forum which mentions it.)


RFT!!!
Dave Kelsen
--
Beleive what you want, but beleive me out of it.

 

I've been passively following this thread as I have a 17 RDX and an 08 Pilot. According to Wikipedia these model years have the VCM:

​​​​​​

Vehicles equipped with VCM[edit]

• 2003 Honda Inspire
• 2004+ Honda Elysion V6
• 2005–2007 Honda Accord Hybrid (JNA1)
• 2005+ Honda Odyssey (USDM) EX-L and Touring Models only (J35)
• 2006–2008 Honda Pilot 2WD Models only (J35)
• 2008–2017* Honda Accord V6 (except EX-L V6 6MT Coupe) *Starting with 2013 Model, VCM operation is 3- or 6-cylinder mode, no longer 3, 4, 6-cylinder operation.[2]
• 2009+ Honda Pilot (all models)
• 2011–2016 Honda Odyssey (USDM) V6
• 2013 Acura RDX V6
• 2013 Acura RLX *3 or 6 cylinder mode
• 2014 Acura MDX *3 or 6 cylinder mode
• 2015 Acura RLX Sport Hybrid *3 or 6 cylinder mode
• 2016 Acura TLX V6
• 2017 Honda Ridgeline

SO my question is two fold. Is this accurate and does a 2014 RDX have the VCM?

 

Yes. All 13-18 RDX's have VCM.

 

I think the implementation changed in the cycle. The 2013-2015 engines would shut down 3 or 4 cylinders depending on conditions. 2016-2018 ones just do 3.

 

I think you mean will run on 3 or 4 cylinders...depending on conditions. The VCM was never programmed to drop 4 cylinders and run on 2...

 

Yes, I guess I meant shut down 2 or 3, running on 3 or 4.

 

I have a 2017 Acura RDX and a 2012 Honda odyssey. The odyssey has had problems with the vcm so installed a VCM muzzled and so far so good.
Mia the 2017 Acura RDX also prone to have issues because of vcm? Should I install a VCM muzzled?

 

The 2016-2018 RDX have the 3-6 VCM that the 2018+ Odysseys have. They are less trouble, so it is your choice. Remember: the VCM saves very little fuel on an individual
basis, but having it on so many Honda models gets them better CAFE ratings. (Corporate Average Fuel Economy)

 

The 2013+ RDXs don't really have issues with the VCM system. Occasionally there might be some due to lack of oil changes/maintenance, but I wouldn't worry about it.

 

As I said above, the 2013-2015 RDX have the same VCM system as the Odysseys through 2017. Supposedly, in 2014, Honda made a change to the piston rings.
However, folks still have had burn plugs and misfire codes in those vehicles made after 2014. So if you have an RDX that is 2016-2018, it does have a different VCM
system. For those VCM Muzzling is probably optional. But if you have a 2013-2015, muzzling is highly recommended.
Keep in mind that RDX owners tend to put far less miles on their cars than Odyssey and Pilot owners. Issues tend to show up after 80k, sometimes not until over 120k.

 

I was wondering about that. Specifically because I have a 2010 Odyssey Touring with the VCM. I know the VCM has engaged when the ECO light comes on.

But I don't see any indication on the RDX that it's gone into VCM mode.
And I don't really notice the rumble/noise issue on the RDX. (I DO notice it on the Odyssey & it's got active noise cancellation.)

 

I realize this is an older thread but I noticed the same...I have an 05 and 16 Odyssey's and they have the ECO light but I haven't seen the same on my 14 and 16 RDX's.
The Ody's are muzzled.

 

This thread got bumped so I thought I might report on the VCM in my wife's 2016 RDX. We had the timing belt service done at 95K because of a noise on cold start (different subject) and the spark plugs were changed. All six came out looking clean with no difference. So the VCM-3 that started with the 2016 RDX (and the 2018 Odyssey) seems to not foul the plugs like it does in the older ones. Of course the Odyssey is bigger, heavier, tends to get loaded with people & stuff, and probably lugs the engine on the highway in 6th gear with VCM active. The comparable vehicle around here would be the MDX.

The noise for those interested turned out to be the tensioner of course, but it was because the water pump was seeping coolant onto it.

 

I currently have (3) vehicles in my personal fleet which are VCM equipped. 2018 & 2013 RDXs and 2019 Ridgeline. Each has an S-VCM controller installed. I'm sure VCM-3 is a better system...VCM only had one way to go, right? Regardless, I much prefer driving with all 6 cylinders firing...all the time.

 

It's funny to watch how people get stuck oil piston rings due to poor oil change intervals and then come up with all sorts of S-VCM to help them. And on my 2013 RDX 200k miles, and the oil concumption in the 4-5k mile interval is zero. In fact, Honda should have made a good piston ring oil drain in the first place to avoid these problems.

 

So, besides the (3) vehicles I currently own equipped with VCM, I've also owned an 11 Pilot and 08 Odyssey which were also VCM equipped. That's (5) different Hondas / Acuras so equipped. I also perform all of my routine maintenance and simple repairs...all of my vehicles are meticulously maintained on time, every time. I can tell you the oil consumption issues of the Pilot and Odyssey (no stuck rings thankfully) had nothing to do with lack of timely maintenance. At the end of my Pilot ownership, I became aware of VCM deactivation devices and decided to give a S-VCM Controller a try. In the short time it was installed in the Pilot, it had an effect on oil consumption...measurably decreasing it.

My 13 RDX has had an S-VCM Controller installed in it, since my 1st week of ownership. It currently has 220k+ miles. At around 140k miles, it began consuming oil as though a "switch had been flipped"...1.5-2qts per interval. Turns out, the S-VCM Controller had also died. The maker sent a replacement which I installed and guess what? Oil consumption returned to negligible per interval. Cause and effect? Yes, I do believe so...especially based on previous experience.

Now, as I stipulated, VCM-3 has in all likelihood corrected the "sins" of previous VCM versions. Even so, any VCM equipped Honda / Acura vehicle of mine is going to get a VCM deactivation device installed. Why? Because I'm not a believer in this "tacked on" technology...that I don't think its a good thing (mechanically) that the engine cycles between shutting on/off half of its cylinders...creating imbalance / vibrations which require counteraction with computer-controlled engine mounts. And...as I mentioned, I like running with all 6 cylinders firing, all the time.

One final point...Honda lost a Class Action Lawsuit in 2013 over excessive oil consumption in which VCM was partially (mostly) to blame. I'm glad you're at 200k miles in your 13 RDX with zero oil consumption with your service regimen...that doesn't mean that many others haven't had issues totally unrelated to how routine maintenance was performed.

 

Of the dozens of engines equipped with the VСM system that I have disassembled, all had two problems: wear of the cylinders and rings due to poor maintenance, or clogging of the oil piston rings, which is also due to poor maintenance. There are no other reasons for oil consumption in these engines, and half of the owners of these cars argued that they maintained their engines well, but in reality they changed the oil every 8-9k miles at places like Walmart or Jiffy Lube.

 

Couple questions. Are you saying the real reason Honda lost that Class Action was due to poor maintenance on the part of the owners? And not VCM as cited?

What are your thoughts on the VCM system in general? Is the "juice worth the squeeze" in your opinion?

 

Honda lost because of its poor piston ring design and long service intervals. But in fact, if the oil was changed more often, there would be no problem at all.

 

Do you know if Honda changed its service intervals as a result of losing that Class Action?

Thoughts on the VCM system in general? Is the "juice worth the squeeze" in your opinion?

 

More excessive oil change fetishists. The real PITA of VCM is fouled spark plugs and check engine lights. Oil consumption was limited to a few years when Honda used "low friction piston rings". Those rings caused oil consumption issues on Hondas without VCM as well.

 

All they did was add more oil drain holes to the piston.

 

No opinion on VCM?

 

There are no problems with VCM, Honda still uses it today.

 

Agreed, Honda still uses it today.

​​​​​​^^^When you posted this^^^ It seemed to me, that you were indicating that VCM systems were fine with no correlation with oil consumption...and VCM deactivation devices are not worthwhile / not helpful with either oil consumption issues -or- at all for that matter.

​​​​​​^^^Which seems to contradict what you posted here^^^

 

I have a '15 RDX with 152K on the clock. I'm still on the original plugs because my gas mileage is still great. Oil changes have been by the 7,500 schedule, but I'm changing that to every 5K now.

Watching a teardown of this engine I learned that the earlier versions of VCM caused issues, but I haven't had any with my car (that I can tell). Wondering if I should go ahead and get a controller anyway, especially since I presumably have the old system (pre '16). And if I do get one, which is the best one to get?

Thoughts?

 

You'll probably get a variety of opinions (good thing).

Mine is that I have directly linked oil consumption to VCM in (2) of my VCM equipped vehicles -and- regardless of whether Honda/Acura has fixed the "sins" of earlier VCM generations...I will always add a VCM deactivation device. Why? Because I don't think its a good thing (mechanically) that the engine cycles between shutting on/off half of its cylinders...creating imbalance / vibrations which require counteraction with computer-controlled engine mounts. It's a tacked-on, over complicated technology / execution which the engine can do without, IMO.

My personal preference is the S-VCM Controller.

 

Do you really want to fix what is not broken?

 

If you aren't experiencing any issues, I would strongly suggest against messing with VCM controllers. I would change those plugs though. 152K is a lot of miles for even the best plugs.

 

Below is an excellent video you posted a while back with another POV on the mechanics of VCM and its potential long term effects. Well worth watching.

 

Worn out was the reason for the oil consumption in this video, 417 thousand miles is no joke.

 

Agree and, BTW I did not see that huge of a difference between left and right cylinder banks.