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Discussion Starter · #1 · (Edited)
I decided to take the plunge and switch from the tried-and-true VCMuzzler to the newer S-VCM. Having had the VCMuzzler on our van for over two years now, I feel as though I thoroughly understand how it works and what an owner can expect on a day-to-day basis from it.

I think it is important that I make one thing clear - I have absolutely no complaints about the functioning of the VCMuzzler. Even with the lowest resistance (blue) we only saw the ECO light on the dashboard a handful of times per year. I don't consider that a meaningful issue or a real cause for concern with respect to all the issues and symptoms regular VCM operation creates. The biggest reason for the switch is the fact that we anticipate that my wife will be making a few long trips this summer without me. And while she is an excellent driver and understands well what all the gauges in the instrument cluster are telling her and knows to monitor them all, I don't think I want her wondering about how far from the truth the temperature gauge is if the needle starts to crawl upwards. She knows about the VCMuzzler on our van and how it manipulates the ECU into thinking the engine coolant is cooler than it actually is.

I haven't seen a lot of pictures of the S-VCM being installed or how it looks in the engine bay, so I thought I'd snap a few pictures as I installed ours. First, here's what you get in the package:







You get the S-VCM controller and 4 little back zip ties to keep everything safe and tidy. It is a small little thing, designed to be only a little bit longer than the factory wiring harness lead to the ECT1 sensor.

Others have mentioned that the power lead to the battery is very small gauge, and they are right. This is the ring terminal at the end of the wire that gets connected to the positive battery post.



I removed both the engine cover and the front piece of the air intake to make it easier to reach both the ECT1 sensor and the positive battery post. The installation itself is quite straightforward and the instructions provided are good. If you follow them to the letter in terms of how to use the provided zip ties, the S-VCM is practically invisible when you look into the engine bay.

In this photo, the S-VCM is visible as a small grey rectangle underneath the wiring harness in the lower left corner of the picture. The black wire stretching across the middle of the picture is the power lead going to the battery (at this point it is not tied up, but just hanging loosely).



The remaining zip ties are used to secure the power wire to the positive battery cable and keep it out of the way. I found that using two of them was quite enough.



Once the installation is completed and the engine cover and air intake are replaced, here is what it looks like in my engine bay:



The S-VCM itself is hidden by the engine cover and the black power wire is very discreet. I believe it would take a well-trained eye to notice it.

For the time being, I am going to keep my VCMuzzler handy, just in case the S-VCM doesn't do what it claims or if the performance is not up to what I am expecting of it. The first drive this morning was just fine, which is what I expected. But I will periodically update this thread with my impressions and thoughts. I'm very much open to thoughts, questions, comments and discussion with my fellow Odyclubbers.
 

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I love the VCMuzzler but, here in Wisconsin the weather changes drastically all the time and I have to keep adjusting it so the ECO light doesn't come on. I still feel like people paid too much for the VCMuzzler. I don't feel like paying close to 100 for anotherome but, if this one works all year long with no adjustment, than I'm sold. Also, my VCMuzzler wasn't working properly for some reason from the beginning. 60-70% of my driving is highway. Sometimes it still comes on. I have noticed a huge difference especially in oil consumption. I haven't had to put any oil in yet which is rare. Usually I'm down a quart. Mine is an 07' by the way. Thanks for your post and pictures! I will have to buy this one for sure!

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Another advantage of the S-VCM is that, should you want/need to enable VCM (say when gas tops $3/gal again ;) , or potentially for diagnostic purposes) temporarily, it is simplicity itself to wire in a switch for the B+ power wire. The S-VCM, when switched 'off' (power disconnected), returns the engine to designed (VCM enabled) function.
 

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Discussion Starter · #5 ·
If anyone is having trouble seeing the pictures embedded in the first post, please have a look at the photo album "S-VCM Install" located in my profile. There are also a few extra pictures in there that I didn't use in the post.
 

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Discussion Starter · #6 ·
I love the VCMuzzler but, here in Wisconsin the weather changes drastically all the time and I have to keep adjusting it so the ECO light doesn't come on. I still feel like people paid too much for the VCMuzzler. I don't feel like paying close to 100 for anotherome but, if this one works all year long with no adjustment, than I'm sold. Also, my VCMuzzler wasn't working properly for some reason from the beginning. 60-70% of my driving is highway. Sometimes it still comes on. I have noticed a huge difference especially in oil consumption. I haven't had to put any oil in yet which is rare. Usually I'm down a quart. Mine is an 07' by the way. Thanks for your post and pictures! I will have to buy this one for sure!
If you feel as though you have the VCM activating too frequently (even with the VCMuzzler), try a greater resistance. The blue resistor is the lowest resistance, followed by orange/brown and then red. That might give you a more satisfactory result.

There is nothing to adjust on the S-VCM - the controller is completely sealed and no user input from the outside is possible. You connect it to the ECT1 sensor, the van's wiring harness and the battery. That's all you can do with it. From there, the programming of the controller itself takes over and you get what you get.

We have not had VCM activate at all over the past two days and our van runs exactly as it did with the VCMuzzler installed (which is to say great). With that said, though, we have not done any driving that could be considered even remotely strenuous - it's been two days of puttering around town with very average ambient temperatures. Our first highway trip fully loaded is scheduled for this weekend, so I think that will be the first real test for us of how the S-VCM controller works under at least some strain. I will be paying close attention to the temperature gauge and whether it behaves any differently as we travel, especially as we get off the highway and re-enter an urban setting.
 

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Installed S-VCM on our newly purchased '15 EX today. It took approximately 5 minutes. Threw a check engine and traction control light. Cleared the code, good to go.

Have a road trip from NC to Disney World on Saturday, so I'll see how it runs then!
 

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Just want to note one thing incase some want to make the distinction. When the ECO light comes on, the engine is not always in VCM. It's just mean that it's being "economical."

But when VCM is on, it always equal to the ECO light being on.

This was true when VCM first came out on the Gen 3. I would think that's still true for the 4th Gen.

I get an ECO light on sometimes for a short while. Then it goes away. IMO, I don't think having the ECO light on at times is a big deal, as it does not mean the VCM is on. Even if VCM was on, it's for a very short while.
 

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Discussion Starter · #9 ·
Just want to note one thing incase some want to make the distinction. When the ECO light comes on, the engine is not always in VCM. It's just mean that it's being "economical."

But when VCM is on, it always equal to the ECO light being on.

This was true when VCM first came out on the Gen 3. I would think that's still true for the 4th Gen.

I get an ECO light on sometimes for a short while. Then it goes away. IMO, I don't think having the ECO light on at times is a big deal, as it does not mean the VCM is on. Even if VCM was on, it's for a very short while.
This is my understanding as well; the ECO indicator appearing in the instrument panel doesn't necessarily or automatically mean that VCM must be active. I don't know if there has ever been a definitive statement of all the criteria used to light the ECO indicator. If there has been, I don't think I'm aware of it. But I believe that for gen 4 Odysseys, the converse of that first statement is true - VCM never activates without the ECO light coming on as well. So the absence of the ECO light can be interpreted as the absence of VCM activation. Having VCM activate from time to time for a little while really isn't a big deal. In that respect, the resistor-based Muzzlers are perfectly fine. We only saw the ECO light a handful of times per year, and only in the summer. I won't stand here and pretend that's not good enough. It absolutely is.

For me, the major improvement S-VCM offers is a more realistic indication on the coolant temperature gauge while still suppressing VCM. That is what I am really after by making this switch. With a resistance-based Muzzler, there is no point in time at which the temperature gauge is showing a true reading (not that a coolant temperature gauge with no graduations or markings is especially accurate at the best of times, but still, the signal from ECT1 is always modified). When I first installed the VCMuzzler, I studied the temperature gauge and learned the "new normal" and feel very confident I could tell when the temperature was getting too high before anything bad happened. And truly, nothing bad ever did happen.

Like I said before, my wife knew about the Muzzler on our van and understands its purpose, but I don't think she is as closely attenuated to the behaviour of the temperature gauge as I am. I am not positive she would know that trouble was coming before it actually happened. I am hoping that the S-VCM controller will remove that potential hazard and keep her and the kids safer when they travel in the van without me.
 

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I'm late to this thread and a newer 4th gen owner (and odyclub member). I have heard about some owners muzzling the eco boost, and wondering what the reasons are and/or detriments to just leaving it alone. I do notice more hesitation as it engages / disengages, and it is an interruption and a distraction more than anything. But is there a long term mechanical concern with leaving it be? I have not noticed any fluctuation in engine temp as was alluded to. If someone could quickly summarize the reasons for muzzling, I would appreciate it. Thanks all!
 

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This is my understanding as well; the ECO indicator appearing in the instrument panel doesn't necessarily or automatically mean that VCM must be active. I don't know if there has ever been a definitive statement of all the criteria used to light the ECO indicator. If there has been, I don't think I'm aware of it. But I believe that for gen 4 Odysseys, the converse of that first statement is true - VCM never activates without the ECO light coming on as well. So the absence of the ECO light can be interpreted as the absence of VCM activation. Having VCM activate from time to time for a little while really isn't a big deal. In that respect, the resistor-based Muzzlers are perfectly fine. We only saw the ECO light a handful of times per year, and only in the summer. I won't stand here and pretend that's not good enough. It absolutely is.

For me, the major improvement S-VCM offers is a more realistic indication on the coolant temperature gauge while still suppressing VCM. That is what I am really after by making this switch. With a resistance-based Muzzler, there is no point in time at which the temperature gauge is showing a true reading (not that a coolant temperature gauge with no graduations or markings is especially accurate at the best of times, but still, the signal from ECT1 is always modified).
When I first installed the VCMuzzler, I studied the temperature gauge and learned the "new normal" and feel very confident I could tell when the temperature was getting too high before anything bad happened. And truly, nothing bad ever did happen.

Like I said before, my wife knew about the Muzzler on our van and understands its purpose, but I don't think she is as closely attenuated to the behaviour of the temperature gauge as I am. I am not positive she would know that trouble was coming before it actually happened. I am hoping that the S-VCM controller will remove that potential hazard and keep her and the kids safer when they travel in the van without me.
That closed the deal for me also when i switched. I had the adjustable resistor type before and end up breaking it (Totally my fault) but when it came time to get a new one the S-VCM seemed like the way to go. I have about 7000 miles on mine and a few hundred on my wife's van. They work good for me.
 

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I'm late to this thread and a newer 4th gen owner (and odyclub member). I have heard about some owners muzzling the eco boost, and wondering what the reasons are and/or detriments to just leaving it alone. I do notice more hesitation as it engages / disengages, and it is an interruption and a distraction more than anything. But is there a long term mechanical concern with leaving it be? I have not noticed any fluctuation in engine temp as was alluded to. If someone could quickly summarize the reasons for muzzling, I would appreciate it. Thanks all!
In a nut shell the long term mechanical concern is,, piston ring issues can developed leading to excessive oil in combustion chamber, which can screw with other thinks like plugs, cats...
 

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Discussion Starter · #13 ·
I'm late to this thread and a newer 4th gen owner (and odyclub member). I have heard about some owners muzzling the eco boost, and wondering what the reasons are and/or detriments to just leaving it alone. I do notice more hesitation as it engages / disengages, and it is an interruption and a distraction more than anything. But is there a long term mechanical concern with leaving it be? I have not noticed any fluctuation in engine temp as was alluded to. If someone could quickly summarize the reasons for muzzling, I would appreciate it. Thanks all!
The extremely short version of it is this: VCM in the gen 4 Odyssey is not well implemented. It wears out the very expensive active engine mounts prematurely, it results in oil getting past the rings on the deactivated cylinders which fouls the spark plugs and damages the rings, hurts power and driveability (which you've already noticed yourself) and at least in my experience, doesn't save all that much fuel. Your worst case scenario is a partial engine rebuild, the cost of which might be covered under an extended warranty Honda offered after a class-action lawsuit against them. There is no good reason at all to leave VCM active; if you've not had any problems you can attribute that more to good fortune than to good design. There are lots of threads and posts dedicated to this.

The temperature gauge fluctuations mentioned above only happen when a Muzzler (of any type) is installed, which is why you haven't noticed them. VCM activation is enabled only after the engine warms up fully, and so people have figured out that if you fool the engine into thinking that it never fully warms up, VCM never gets activated. This technique is perfectly fine and safe - thousands of people have driven millions of miles with overwhelmingly positive results. The only problem is that the coolant temperature gauge uses the same sensor signal as the VCM system. So if you install a Muzzler (of any type), the temperature gauge will show that lower (inaccurate) engine temperature. So you need to pay special attention to the coolant temperature gauge as your van starts to work harder and get hotter.

I hope this helps.
 

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Discussion Starter · #14 ·
An update after our first lengthy road trip this weekend:

The S-VCM definitely suppresses VCM activations very well - I never saw the ECO indicator even once during the whole trip. The coolant temperature gauge does behave a little bit differently than with the VCMuzzler.

Upon startup, I don't think the S-VCM does anything at all to the ECT1 signal. My impression is that the needle on the temperature gauge swung upwards more quickly than with the VCMuzzler, probably closer to what it did bone stock before I got the VCMuzzler. As the engine reached its normal operating temperature, the needle also swung a little bit higher, presumably because the S-VCM will let the gauge go all the way up to 166F. But after that, the needle stayed rock steady and the ECO light never came on.

I was especially interested what would happen when we got off the highway and re-entered the stop-and-go traffic of an urban setting. With the VCMuzzler, if it was hot enough and the traffic slow enough, we would sometimes get the ECO indicator coming on for a brief time. That did not happen this time around; the temperature gauge stayed exactly where it had been the entire time before reaching the city. It's impossible that the engine temperature did not go up at all, but it must not have reached the danger point where the S-VCM should turn itself off and let the temperature gauge shoot upwards to warn of a potential overheat condition.

I admit this impression-based commentary feels a little light and prone to confirmation bias ("He's already sunk money into the thing, so of course he's going to want to see it working the way he expects."). I think maybe over the summer I might reinstall the VCMuzzler and try to take some pictures or video of the temperature gauge in action, and then do the same with the S-VCM so that we can have a more objective basis for comparision. It would also be helpful to get some live data from an OBDII scanner, but I don't happen to own one of those right now. But for now at least, I am very pleased with the way the S-VCM controller works.
 

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Is there a need to deactivate?

I have a 2016 Odyssey 6 speed. Cylinder deactivation on this vehicle engages and disengages imperceptibly - you can't feel it at all. No bumps, jerks or interruptions in smoothness that I can feel. Nada.

I have a vacuum gauge and a scan gauge on this vehicle, so I can see exactly when cylinders are deactivated and see the direct impact that deactivation has on mileage. The scan gauge reads instantaneous fuel mileage in tenths of a mpg, every second or so. It is easy to see when cylinder deactivation mode is operating. It is not so easy to see whether two or three cylinders are deactivated, but in time I have learned to see this too.

I have been using vacuum gauges on my vehicles since the early 80's. Vacuum gauges saved me gas by helping me to see the effect of small throttle movements - when I paid attention, that is. With the scan gauge and the vacuum gauge, I see that small throttle movements can significantly affect fuel mileage with little difference in vehicle acceleration. I have learned not to try and accelerate while going up hill, for example, and to speed up before reaching the bottom of a hill. And to lift off the throttle immediately when a traffic light changes to red. Depending on surrounding traffic.

When using the cruise control, cylinders remain deactivated longer than when using the throttle to control cylinder deactivation mode. The gas mileage while in cylinder deactivation mode is roughly 10% better when two are deactivated, and perhaps 15% better when three cylinders are deactivated.

No doubt that earlier years' cylinder deactivation have engagement and disengagement issues, so in this situation, deactivation is likely justified. But I can see no valid reason to disable cylinder deactivation on my vehicle. A dealer could argue that disabling cylinder deactivation would void the 5 year 60k factory powertrain warranty by disabling cylinder deactivation. If this is the case, one should attempt to get the dealer to either deactivate it or approve the fix beforehand. I also had a C7 Corvette stick shift with cylinder deactivation and that engaged and disengaged smoothly, but there was an increase in engine and power train vibration when it was active, that others found objectionable, but it could easily be turned off electronically. Nevertheless, these owners complained about it incessantly, but I could never figure out why.

I do see where it could possibly affect cylinder wear over hundreds of thousands of miles, but that is unlikely. Power output is in the low torque/power range when cylinder deactivation is in play, where combustion pressures are low - like around 10%-20% of available torque (and BMEP - Brake Mean Effective Pressure). Cylinder wear increases at high power and BMEP, not at low power and torque.

I had 248k on my 2000 Odyssey and was still getting 4500 - 5500 miles per quart of oil when a cow ran into this vehicle, totaling it. I might have gotten 6000 - 7000 miles per quart when it was new. I used synthetic Mobil One Extended Life oil for the last half of the vehicle's service life, often changing it near the recommended 15k change mark (after several conversations with Mobil engineers). Before that, 4000 miles was my change limit using several brands of conventional oil. In other words, cylinder wear over time was minimal with the 2000 Odyssey. If it was 2-3000 miles per quart, that would have been acceptable in an older vehicle with that mileage. And - the decrease in oil mileage could very well be the result of the hardening of the valve seals. Most manufacturers consider perhaps 1000 miles or thereabouts per quart acceptable on cars with remaining factory warranties. in other words, the ECO mode shouldn't cause a significant wear problem. Not to worry.

My complaint with cylinder deactivation is that keeping the engine in cylinder deactivation mode is touchy and very difficult to control with the throttle. In the range where deactivation comes into play, the throttle is overly sensitive. I wish I could fix THAT by altering the throttle curve in the deactivation and cruising range. I see very little increase in torque or acceleration in the last quarter of throttle movement, which seems wasted movement, to me. For years, throttle control has been designed by car manufacturers to cause the vehicle to accelerate strongly during the first quarter of throttle movement, making a vehicle seem and feel more powerful - but for me, that is no big deal.

If cylinder deactivation works smoothly and imperceptibly, as it does for me, I see no valid reason to arbitrarily disable it with aftermarket "fixes".

With my neighbor's 2014 Odyssey, 68k, deactivation is not smooth, according to him. I told him about the fix and he is considering it.
 

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Discussion Starter · #16 · (Edited)
Is there a NEED to deactivate VCM? "Need" is a very strong word, so the direct answer there is probably no. But the best answer is probably a little more nuanced than that.

It's really a case of different strokes for different folks - I hope the performance you're getting is now is what you will continue to get for as long as you own the van. Lots and lots of people do. But more than a few people don't, and this is for those who don't want fate or (mis)fortune to decide which group they'll fall into. Because it doesn't seem as though it's possible to know in advance whether or not you will have troubles. That's pretty much all it comes down to, at least until problems arise. The decision-making criteria change after being presented with a big repair bill. ?

There is no doubt that driving habits have a major impact on fuel consumption, regardless of any other technology. Being smart, efficient and proactive on the road is just good driving, and I'm totally with you on that.
 

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It seems like one of the most popular threads on this forum are those concerning the Odyssey VCM and the installation of various after market VCMuzzler and S-VCM. Posters make it sound that if I don’t install one of these devices that an Odyssey engine is going to self destruct. To set the record straight my 2005 Odyssey EX-L was 13 years old and had 102,000 miles when I sold it. The only after market modification I made to that vehicle was the installation of a K&N Air filter which I cleaned every 20,000 – 30,000 miles. During those 13 years of ownership the only major problem I had with that Odyssey other than routine maintenance, and Tires and Brakes, was leak in the refrigerant line to the rear AC condenser. The engine never burnt any oil between oil changes, had any problem with spark plugs, motor mounts, or any of the other rather serious problems posters associate with the VCM system. As I remember my 2005 delivered between 18 to 24 Miles per gallon depending on where and how we drove it. I wonder if the Honda VCM system is so bad why after all of these generations of Odysseys does Honda still use the system?
 

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Discussion Starter · #18 · (Edited)
It seems like one of the most popular threads on this forum are those concerning the Odyssey VCM and the installation of various after market VCMuzzler and S-VCM. Posters make it sound that if I don’t install one of these devices that an Odyssey engine is going to self destruct. To set the record straight my 2005 Odyssey EX-L was 13 years old and had 102,000 miles when I sold it. The only after market modification I made to that vehicle was the installation of a K&N Air filter which I cleaned every 20,000 – 30,000 miles. During those 13 years of ownership the only major problem I had with that Odyssey other than routine maintenance, and Tires and Brakes, was leak in the refrigerant line to the rear AC condenser. The engine never burnt any oil between oil changes, had any problem with spark plugs, motor mounts, or any of the other rather serious problems posters associate with the VCM system. As I remember my 2005 delivered between 18 to 24 Miles per gallon depending on where and how we drove it. I wonder if the Honda VCM system is so bad why after all of these generations of Odysseys does Honda still use the system?
With all due respect man, I have no interest in rehashing these tired conversations. They've been had a dozen times over in other threads - and in minute detail. I know no one feels like reading threads with thousands of posts in them, but if you really care to know the answers you'll put in the time.

The basic premise of this thread is that I (as a gen 4 Odyssey owner) have put in the time and effort to thoroughly research what VCM2 does and how it does it. I have researched, read, asked and studied far beyond this one forum, and I have reached the conclusion that disabling VCM2 is the correct choice for my family's vehicle. This means absolutely nothing for anyone outside my family. I'd encourage everyone else to do the same kind of research. Don't trust any one person or source exclusively, least of all me. No one out here on the interwebs knows me from Adam. Take anything I say or claim and test it against other sources of information. If you find me credible, test what others say against what I say.

Since I am operating here on the premise that VCM2 should be disabled, I am trying to convey how the different devices behave. I am not trying to convince anyone to do one thing or another - that's up to you. Your van, your choice. If you are having a great ownership experience without the use of a VCMuzzler or any of its counterparts, I'm happy for you. And you should definitely share that with the group because we need that balance of experiences - just do it in another thread.
 

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Just bought a 2011 Touring Elite with 85k miles. The owner had never heard of this problem and never experienced any issues. Before I even took delivery I ordered a S-VCM because I hope to keep the van for a long while. My kids are 4.5, 1.5, and -.5. If my engine ends up not needing it then it was an insurance policy and I'm OK with that.
 

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I suspect there may be two issues at play. 1) cylinder carbon 2) engine mount wear. I drive like you do, with a very steady foot on accelerator, trying to drive a steady speed, looking far ahead to minimize the energy lost to breaking. I never feel the VCM go in or out probably because I'm not asking for larger amounts of power. Now if I had more of a lead foot, accelerating quickly at lights, between cars, etc I can see the engine rocking when accelerating from a dead stop and each time the VCM goes in out out since this driving style would create a noticeable step increase or decrease in engine torque. This could increase the cycles on the engine mount creating accelerated wear on the engine mount, and early replacement. My odyssey only has 25K miles so its too early for either issue to be present. I don't have enough data to evaluate the cylinder carbon issue. There are all kinds of factors at play. Does the cylinder shut off cool those cylinders enough to affect combustion when turned back on? Are the rings adequate for the temps and pressures? I read Honda used the new rings for two years that lead to the class action lawsuit and an extended warranty for those years. Does the engine shut off lubrication to deactivated cylinders? Are cylinder walls over-cooled in deactivated cylinders? Are pistons over-cooled in deactivated cylinders? Is the deactivation complete keeping all fuel out of deactivated cylinders. I know that the new oils and engine tolerances are significantly better than 20 or 30 years ago. I have diesel engines at work that require special break in oil with reduced lubricating properties or they don't break in right. The new oils won't let the rings seat and bearings can take 500 hours to seat with new oils when they should be seated in the first 50 hours. The new oils are good and should protect the engines for hundreds of thousands of miles with regular changes. The new oils may lubricate well but they do not stop carbon build up in diesel engines. We've had diesel engines at work that spent 500 to 1000 hours at very low loads leading to low combustion chamber temperatures leading to wetstacking and stuck rings with excessive carbon build up. We've had to overhaul engines from wetstacking build up that wouldn't burn out under load. The engine problems described by various posters could be the result of carbon build up though I don't know the exact cause or failure mode if in the VCM system that would allow the carbon to build up in the cylinders.
 
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