[dr bob]

I've had a VCMuzzler installed since the car was about a year old. I get the occasional ECO light after sitting in a hot-soak traffic situation, but it goes off almost immediately once the car is moving or the fans come up to speed to shed the excess heat. No CEL's.

The temp gauge is more an idiot gauge than an accurate indicator of coolant temp, even without the VCMuzzler installed. The actual temp range between about 180º and maybe 220ºF causes minimum gauge needle movement regardless. The VCMuzzler moves that gauge-movement range slightly. But since it has no scale, all that changes is the needle position. At the high end of the scale, the resistor adds about 10ºF to the less-responsive-needle window.

Were I starting from scratch, I'd probably choose one of the "smarter" units. At this point though I'm unlikely to change out what I have installed already. I, like a large majority of drivers, only look at the temp gauge once in a while, or when the cluster lights up and gives a high-temp alarm. That ten degree error at one (of the three...) engine coolant temp sensors is unlikely to make a difference in how I respond the gauge reading, although it will delay the temp alarms by maybe ten degrees. Critically, it does not change the fans operating temperature; that duty goes to the incoming coolant temp sensor, rather than the outlet temp sensor when the VCM defeat devices connect.

 

[dr bob]

I'm using one too, around 35k miles with it and no trouble. A couple times in stop and go on really hot days the system seemed to want to engage but stopped immediately as soon as I started rolling,

I'm of the feeling that it's probably Good Idea to let the VCM system components like sensors, solenoids and actuators, get a little exercise once in a while. The amount of time that the ECO light is on in those hot-soak driving condition is a tiny tiny fraction of a percent of total engine run time. It's certainly no risk to combustion or piston rings even in high-miles engines. In my amateur opinion anyway.

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FWIW, the actual scope of operation of the VCM system is pretty impressive when you think about it. Honda engineers did a pretty good job picking up the ugly byproducts of the missing cylinder-firing, and without counter-rotating "balance shafts" or other complexities. Setting drivability issues aside, like odd transmission shifting and surging, we generally don't see serious problems until there are some oil control issues that happen as the oil scraper rings wear in the bores. Owners can delay those effects with frequent synthetic oil services from birth, so that the rings see less wear and any oil ash and coke deposits in them get washed out quickly. For me, the drivability and odd shifting under VCM were the symptoms I wanted to eliminate; the engine oil in ours gets changed at about the 50%-remaining-life indication on the Maintenance Minder. Plus it's had synthetic oil in it since it arrived home the first time from Honda. Ring and bore wear are not a concern for me.

I'll likely get some bore-scope pictures when I change the spark plugs in maybe eight years or so at the rate we aren't piling miles on the car. I expect see fresh hone marks/hatching on the cylinder walls at that time, consistent with the results seen in previous engines that received the same service protocol. I expect to still see the break-in coating on crank bearings too should I get into it that deep.

 

[dr bob]

I have a 2012 Honda Pilot Touring 4wd, my problem is accelerating issues .I can be cruising 40-45 mph and I want to pull out and pass, and sometimes this vehicle just doesn't have enough power unless I floor it....to get it to start accelerating...my question is will this help? and where do I buy it at it? which resistor do you recommend?

I'm not sure that either will solve your power issue. You can experiment some by tapping the brake pedal slightly before demanding the power, as that will cause it to drop out of VCM momentarily.

As far as which option for VCM eliminator, the S-VCM is the currently recommended option. It offers a couple benefits around over-temp gauge accuracy, since the sensor it's trying to fool is the return coolant from the radiator. That one plus two more combine to drive the gauge in the instrument cluster.

I have a VCMuzzler installed, and the gauge isn't a big enough issue to warrant the upgrade. But were I starting from scratch, the S-VCM is weapon of choice these days.

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You might share the mileage and history on the car. One of our regular contributors shared a similar symptom, and ended up replacing PCV and EGR valves to restore original performance. Neither is a particular chore to replace if you are comfortable with the tools. The PCV is plastic and can get a little crispy with age. Plus if you use conventional (not full synthetic) oil and only on the MM schedule, the O-rings can get stuck from varnish in the bore it fits in. Of course that varnish is the same stuff that's affecting the PCV operation inside the valve, making replacement more critical.

 

[dr bob]

How did the plugs look? How about that PCV valve? Those, especially the plugs, are valid telltales of VCM-related oil-control issues. Cylinders 1-3 are the most-activated VCM's cylinders, and oil control issues show up with darker and maybe oil-coked plug tips. Do a bit of forum searching on the EGR replacement and consider that experience. IIRC, it was member AVC who shared his analysis and results here. Maybe that will help with your searching.