Can Honda VCM problems be fixed with short OCi's?

[candoo]

Hi everyone:

I just got a letter in the mail from Honda Canada in regards to a warranty extension on my 2013 Odyssey. It's entitled " Engine Misfire Due To Carbon fouling of Spark Plugs"

The problem, as stated in the letter, reads:

"On certain Honda vehicles equipped with V6 engines with Variable Cylinder Management (VCM-2) , the cycling of the cylinders under certain drive conditions allows for spark plug cooling, which may result in carbon fouling of the spark plugs. . When the fouling becomes severe, the Malfunction Indicator Light (MIL) will come on, and one or more Diagnostic Trouble Codes (DTC P0301, P0302, P0303, or P0304) will be stored in the vehicles Powertrain Control Module."

Does anyone here know if this is the same problem that relates to long oci's as per the oil life minder (as told by BITOG members in other threads). In other words, is this problem in the warranty extension letter just an end result of not changing the oil often enough in these Honda V-6 VCM engines?

Thanks

 

[JHZR2]

I don't see how cold spark plugs growing carbon relates to anything else oil related.

I also don't see why Honda doesn't change the deactivated cylinders more often...

 

[demarpaint]

Changing your oil early will not stop spark plugs from carbon fouling. There were sludge issues associated with earlier model years using this type engine, and earlier oil changes using synthetic oil helped them. But that was sludge not carbon fouled plugs. I thought that issue might have been resolved, although I'm not sure.

 

[Trav]

The earlier VCM-1 engines had different problems. The oil has nothing to do with the problems on VCM-2 engines.

 

[candoo]

The earlier VCM-1 engines had different problems. The oil has nothing to do with the problems on VCM-2 engines.

So then, can I assume that The VCM2 engines don't have the OLM oil life issues of the VCM1 engines, but rather, they now have a different problem -- the spark plugs foul on them?

 

[Trav]

I don't see the same kind of deposit issues with the VCM-2 but i would keep an eye on the fill hole, it it begins to look like varnish down there shorten the OCI.
I still would not run dino in these engines.

On the VCM-2 they bring the other bank into play to make the engine smoother (they claim).
IMO they are also trying to correct the deposit issue with the VCM-1 but they will not admit that, it opens to many doors.

I would run Redline SI-1 in small doses in every tank, it is approved for constant use or Techron system cleaner every 3K to possibly keep the carbon issue at bay.

 

[Clevy]

Candoo

Trav is a real mechanic and has forgotten more than most will ever know. He's an expert so I'd follow his recommendations to the letter.
Just sayin....

 

[ARB1977]

If carbon fouling is an issue, why not install an oil catch can between the pcv system.

 

[Trav]

These use an internal PCV system with a replaceable valve so fitting a catch can isn't possible.
Is the issue rooted in breathing from the PCV system? I have no idea.

The later engines don't appear to have the same clogging issues in the PCV system like the earlier ones but it maybe to early to say for sure.
If they are having problems then it might be back to square one with short OCI and frequent PCV valve changes.
Honda has been working on this issue for some time now.

With most of these engines being still under warranty it may be some time before i get into one with his problem but as i understand it the fix for these is a long block not just a clean up.
My only advice is to keep an eye on the fill hole for the first signs of varnish or deposits. Use a synthetic oil and replace the PCV as part of the maintenance program.

 

[mclasser]

Short OCI's won't cure anything. Some folks over on Piloteers.org said using a heavier oil like 0W-40 seems to lessen VCM vibrations. Others said disconnecting a certain oil pressure sensor totally disables VCM. I'd be apprehensive to try the latter.

 

[Trav]

Originally Posted By: mclasser
Short OCI's won't cure anything.

A more frequent OCI does keep the deposit issue under control. Deposits in these engines clog the internal passages under the valve cover for proper PVC operation.
While it may not "cure" the issue a shorter OCI goes a long way in preventing it.

0w40 does little or nothing for VCM vibrations on the VCM-1 engines, its inherent to the design hence the use of hydraulic engine mounts. Later VCM-2 engines got both banks into the act which helps reduce vibration.
Disconnecting the VCM pressure sensor does disable the VCM but also puts it in limp home mode with CEL and oil pressure light.

I have posted a lot of pictures over the years of these engines inside, you can still find some.

 

[SteveSRT8]

You got to hand it to the 'early adopters' who are out working the bugs out of these technologies for us.

 

[Trav]

IMO Honda should have taken a lesson from GM's 8-6-4 fiasco, their first failed attempt at this technology.
GM was smart enough to shelve the technology until it was ready for prime time, on the other hand Honda put out a very complex and sketchy system and used consumer vehicles as a test bed.
When it came to light there were serious issues they scrambled like mad to correct them and created new issues.
Instead of shelving it till they got it right and losing a few CAFE credits they foisted it once again on the consumer.

Today it seems GM and Chrysler have really good systems. Honda in spite of their whizzbang engineering skills still doesn't seem to be able to get this right.
I would go as far to say they actually ruined a very good and proven engine with this and charged a premium for it.

Still a little class action law suite provides some relief but owners of the early version got left holding the bag anyway.

 

[demarpaint]

Originally Posted By: SteveSRT8
You got to hand it to the 'early adopters' who are out working the bugs out of these technologies for us.


That is a sickening fact of life unfortunately. It is also the reason why I stay clear of any "new or advanced technology" for a few years. Timing it is tricky, but if you catch it right you can save yourself a lot of grief.

 

[refaller]

My generation 1 VCM works flawlessly. At 130,000 miles, it did just burn a quart of oil over my 8,000 mile OCI. It has had a steady diet of synthetic over it's life however and I will only be truly satisfied if it lasts over 200,000 miles at which point I will get rid of it anyway.

ref

 

[Trav]

You are lucky. The engine is obviously not seeing the conditions that causes the varnish and deposits.
Not every one of these engines sludge but the ones that do all seem to have similar operating conditions.

If you ever get a VSA and CEL together and it runs terrible post back. When it happens it happens just like that, from one minute perfect and then it comes out of nowhere usually when the vehicle comes to a stop like a red light.

 

[sciphi]

Seems like the trick to preventing carbon fouling is to do an Italian tuneup once every tank of gas or so. After dropping the kids off at daycare, that is!

 

[Trav]

Your guess is as good and anyones.

 

[willbur]

I've got a 2008 v6 Accord with the 3-4-6 version of VCM. No problems @35000 miles, but am waiting for the alleged VCM issues to appear. Just how prevalent are these problems? Local honda service manager says infrequent and seems to be limited to cars with poor maintenance. I read about the issue and don't know what to think...

 

[Trav]

Your not alone Honda doesn't know what to think either it would seem.
These service managers all tell a different story but when you break it down poor maintenance seems very unlikely.

Some early VCM-1 had burnt on deposit and varnish issues caused by excessive heating of the front bank in eco mode.
This caused hard sludge that clogged the internal PCV system and made matters even worse.
Changing the oil at OLM or 7500 mi didn't help, no PVC valve maintenance was recommended by Honda, oil and fuel additives are taboo says Honda so where exactly is the lax maintenance?

Some VCM-2 engines have carbon problems, still no PCV maintenance or additive recommendation AFAIK.
Again what lack of maintenance? I don't know anything you can do to prevent carbon buildup and stay within their maintenance guidelines.

Certain operating conditions seem prevalent in engines that have issues.
Soccer mom type duty, lots of cold starts, short runs and when the engine does see a long run times its on the highway in eco mode.
Not every one of these engines is going to have problems, how many will is anyones guess.

It seems that the less time the engine is in eco mode the better, IMO running Redline SI-1 a few ounces per tank or a least a bottle of Techron in the tank every 3K and changing the PCV valve every 30K will help.
Varying the amount of time the engine is allowed to remain in eco mode like on the highway by kicking it down a gear and getting some revs wont harm it either.
No need to beat on the engine just get it out of eco mode frequently on a trip.

This is just my opinion, i really don't have any answers, just some ideas.