Drive Accord Honda Forums banner
1 - 20 of 23 Posts

·
Registered
Joined
·
410 Posts
Discussion Starter · #1 ·
I had gotten a "mixed" reaction in a thread I started about my warning beeper/chime for the seatbelts/"fob in car" warning here: [URL="http://www.driveaccord.net/forums/showthread.php?p=215787]http://www.driveaccord.net/forums/showthread.php?p=2157874[/URL]. I've also noticed a marked increase in the VCM "boom" and vibration in the last couple of months, so when I took my car in for its first oil change, I had these issues checked (and my dealer's service manager and a tech. spent a couple of hours on TechLine), and I thought that their findings and information might be useful. If any Honda techs (HondaTechAV6 et. al.) are monitoring this, please "chime" in and confirm this stuff: :lmao:

  1. "Accord"-ing :) to Honda, they've found that the chime is sensitive to colder temperatures, so it may sound odd the colder the temperature falls! (Probably no action will be taken on this, but who knows? :dunno:)
  2. More importantly, the bushings on the Active Engine Mount are less pliable in the cold, so therefore, the operation of the VCM will be more easily noticed at lower temperatures!

    My car had been sitting out in ~-10-degree temperatures for several hours, and on the initial test drive to confirm the problem, both the Service Manager and his tech. were surprised by the VCM kicking in after the car warmed. (50mph, especially in "ECO"-mode, with the T/C locked up and 6th-gear engaged, gets a little tiresome for one's right foot if the traffic doesn't allow you to engage cruise, and you have to maintain that speed for an extended period; of course, the ACC on my Touring helps in this situation.) Back at the dealer, a fresh shipment of 2014 Accords was being unloaded from the transporter: a V6 NAVI Sedan was taken aside, prepped, then parked in the shade on the windy side of the building, then a few hours later, both guys did the same drive, same setup, and the brand-new, fresh-off-the-truck car exhibited the same noise!

    TechLine opened a case, and recommended a VCM/Active Engine Mount Function Test, which (again, please advise if I'm incorrect, techies) is conducted on the dyno while the car is hooked to the HDS; I believe that they got the vibration while on the dyno, 50mph (with the hood up and the engine resembling a paint shaker, I'm certain), and after the tech was able to disable VCM through the HDS or by "pulling the plug" mechanically, there was no vibration, and all tests passed after VCM was re-enabled, so fortunately, no issues with the transmission, as others have noted on this board. Then they brought my car and the other new car inside for a couple hours, then took both on the same drive after letting them warm up inside, and the vibration was there in both cases, just much less noticeable. (Thinking about things further, I realized that the VCM operation has always seemed more pronounced on the way home from work, after the car has been sitting out all day! :blush: :rolleyes: So if you're having a consistent problem with your car's VCM operation and your car isn't normally garaged, see if you can beg or borrow a couple of hours in a garage, then road-test the car and see if the VCM operation isn't as obvious.)

I guess given the problems that plagued early VCM implementations, I'd rather have a more robust engine mount than one which will fail out-of-warranty, with a $500-plus-labor cost to replace it. However, I did state my surprise that Honda wouldn't have extreme (think northern Canada)weather-tested this stuff!

So if you're bothered by your car's VCM operation, particularly if you're in the part of the country which has been most resembling the Arctic since the middle of last December, see if your dealer will open a TechLine case; perhaps if Honda has enough customer complaints, they might be compelled to address this problem via a TSB.
 

·
Former H Master Tech
Joined
·
318 Posts
"Retired" Honda master tech here. Sounds like you had a knowledgeable tech who actually took the time to properly diagnose your car. You would not believe the amount of [email protected] techs are at most dealers, usually only a handful that actually know what they are doing.

The chime noise is somewhat normal in those kind of weather conditions. Its a small speaker located in the dash that is about 1" around with a plastic cone. That kind of cold weather would cause it and the diaphragm to shrink and have almost no movement making a "shriek" noise. I use to have a Jaguar that made the most god awful noise when it was really cold too.

VCM has been in Honda V6s now for 10 years and has had complaints since day one...that being said this is a much better version than what debut years ago. You are literally creating a misfire in several cylinders in order to save gas, your going to feel or hear the slightest things at times. Most people don't realize that when you enter VCM mode your engine wants to violently shake which would translate to major vibrations felt throughout the car, but the electric motor-mounts are counteracting the movement. The problem is these motor mounts do wear out rather quickly and don't react well to extreme temperatures. The more miles you put on your V6 the more your going to feel the VCM unfortunately due to the mounts wearing. Now on the flip side, you would see a substantial drop in HWY fuel economy without it.

VCM is activated through switches and oil pressure when your PCM says its within those permitters. Two ways it can easily be deactivated; by disconnecting the oil pressure switch located on your rear bank or de-activating it with the HDS (which is only temporary unless they have installed some new software that I'm not aware of). We use these methods when trying to problem solve issues with the engine, removing the possibility that VCM might be culprit.
 

·
Registered
Joined
·
416 Posts
If I disconnect the pressure switch, will there be a plethora of warning lights? Will the car behave oddly, or will it drive as smoothly, just running more cylinders? Finally, would the transmission still run the car at the higher rpms needed for the 3 cyl mode even though the VCM is deactivated?

Thanks for the useful information!


Sent from AutoGuide.com Free App
 

·
Former H Master Tech
Joined
·
318 Posts
If I disconnect the pressure switch, will there be a plethora of warning lights? Will the car behave oddly, or will it drive as smoothly, just running more cylinders? Finally, would the transmission still run the car at the higher rpms needed for the 3 cyl mode even though the VCM is deactivated?

Thanks for the useful information!


Sent from AutoGuide.com Free App
To be honest with you, I have never done it on a 9th gen but I don't think it would. The Pilots/Odysseys do not turn any dash lights on and drive perfectly fine without it... all 6 cylinders firing at all times when disconnected. You can try it, it wont hurt anything to disconnect it and if there was any lights they should turn off within two cycles of the ignition.
 

·
Registered
Joined
·
1,695 Posts
Just out of curiosity, would disconnecting the oil pressure switch on the rear bank also affect normal VTEC operation? Or is there a separate switch associated with VTEC? If they share the same one, wouldn't that cause major issues above 4900 rpm (like VTEC not engaging at all, or heaven forbid, VTEC engaging on one bank but not the other which seems like it would be catastrophic to the engine)? I ask because I'm looking at getting a 9th gen V6 in the next few months and this sounds tempting to do since I do a lot of city and sub-50 mph cruising and would prefer not to engage VCM if it causes noise/vibration issues at those speeds.
 

·
Former H Master Tech
Joined
·
318 Posts
Just out of curiosity, would disconnecting the oil pressure switch on the rear bank also affect normal VTEC operation? Or is there a separate switch associated with VTEC? If they share the same one, wouldn't that cause major issues above 4900 rpm (like VTEC not engaging at all, or heaven forbid, VTEC engaging on one bank but not the other which seems like it would be catastrophic to the engine)? I ask because I'm looking at getting a 9th gen V6 in the next few months and this sounds tempting to do since I do a lot of city and sub-50 mph cruising and would prefer not to engage VCM if it causes noise/vibration issues at those speeds.
No, VTEC uses it's own switch and actuator... Completely different system just operates similarly in that regard. Everything else should operate normally
 

·
Registered
Joined
·
1,695 Posts
Awesome :) Thank you!
 

·
Registered
Joined
·
416 Posts
Not to disagree with what your saying as I simply do not know, but the guys on the ody forum said there is a CEL light and occasionally a VSA light. Also they said there was a hesitation once every drive cycle. I'm not sure what they mean by drive cycle, but I certainly want to try it on my 8th gen. I will wait until I go back home though bc I can't afford to be without a car should something go wrong. Thanks!!


Sent from AutoGuide.com Free App
 

·
Former H Master Tech
Joined
·
318 Posts
When they say drive cycle, they are referring to each time you cycle the key on. The car would do that each drive cycle because it actually tests all systems each time you turn it on. It is entirely possible that a dash light may come on as all electrical systems communicate to each other within your car through B-CAN. Changes in voltages and resistance in one unit can effect another causing dash lights to come on. I have never left a car with VCM off, only test driven them and never had a light come on... But that's now to say that can't happen.

Now the newer odyssey and 8th gen Accords have two phase VCM which will deactivate 2 or 3 cylinders based on the speed you are traveling and load. 9th gen accords only have single phase (better IMO), so it is a little bit of different system. I promise you nothing will be damaged or hurt by unplugging the VCM switch, so there is no harm in trying it.
 

·
Registered
Joined
·
1,570 Posts
I had gotten a "mixed" reaction in a thread I started about my warning beeper/chime for the seatbelts/"fob in car" warning here: [URL="http://www.driveaccord.net/forums/showthread.php?p=215787]http://www.driveaccord.net/forums/showthread.php?p=2157874[/URL]. I've also noticed a marked increase in the VCM "boom" and vibration in the last couple of months, so when I took my car in for its first oil change, I had these issues checked (and my dealer's service manager and a tech. spent a couple of hours on TechLine), and I thought that their findings and information might be useful. If any Honda techs (HondaTechAV6 et. al.) are monitoring this, please "chime" in and confirm this stuff: :lmao:

  1. "Accord"-ing :) to Honda, they've found that the chime is sensitive to colder temperatures, so it may sound odd the colder the temperature falls! (Probably no action will be taken on this, but who knows? :dunno:)
  2. More importantly, the bushings on the Active Engine Mount are less pliable in the cold, so therefore, the operation of the VCM will be more easily noticed at lower temperatures!

    My car had been sitting out in ~-10-degree temperatures for several hours, and on the initial test drive to confirm the problem, both the Service Manager and his tech. were surprised by the VCM kicking in after the car warmed. (50mph, especially in "ECO"-mode, with the T/C locked up and 6th-gear engaged, gets a little tiresome for one's right foot if the traffic doesn't allow you to engage cruise, and you have to maintain that speed for an extended period; of course, the ACC on my Touring helps in this situation.) Back at the dealer, a fresh shipment of 2014 Accords was being unloaded from the transporter: a V6 NAVI Sedan was taken aside, prepped, then parked in the shade on the windy side of the building, then a few hours later, both guys did the same drive, same setup, and the brand-new, fresh-off-the-truck car exhibited the same noise!

    TechLine opened a case, and recommended a VCM/Active Engine Mount Function Test, which (again, please advise if I'm incorrect, techies) is conducted on the dyno while the car is hooked to the HDS; I believe that they got the vibration while on the dyno, 50mph (with the hood up and the engine resembling a paint shaker, I'm certain), and after the tech was able to disable VCM through the HDS or by "pulling the plug" mechanically, there was no vibration, and all tests passed after VCM was re-enabled, so fortunately, no issues with the transmission, as others have noted on this board. Then they brought my car and the other new car inside for a couple hours, then took both on the same drive after letting them warm up inside, and the vibration was there in both cases, just much less noticeable. (Thinking about things further, I realized that the VCM operation has always seemed more pronounced on the way home from work, after the car has been sitting out all day! :blush: :rolleyes: So if you're having a consistent problem with your car's VCM operation and your car isn't normally garaged, see if you can beg or borrow a couple of hours in a garage, then road-test the car and see if the VCM operation isn't as obvious.)

I guess given the problems that plagued early VCM implementations, I'd rather have a more robust engine mount than one which will fail out-of-warranty, with a $500-plus-labor cost to replace it. However, I did state my surprise that Honda wouldn't have extreme (think northern Canada)weather-tested this stuff!

So if you're bothered by your car's VCM operation, particularly if you're in the part of the country which has been most resembling the Arctic since the middle of last December, see if your dealer will open a TechLine case; perhaps if Honda has enough customer complaints, they might be compelled to address this problem via a TSB.

Wow, I have an 09 and no issues... just wonder how this happens normally. I am going to post in the summer a cool way to install an engine strut on the cheap. Very similar to my 2000 Toyota. In fact I'll do a side by side.
 

·
Registered
Joined
·
416 Posts
Thanks so much for the help! When you did test drive them, did you notice anything different? I would like to do this bc I want my highway rpms to be lower, to reduce stress on the motor mounts and reduce stress on the transmission But my thought is that even if I deactivate the VCM, the transmission is still programmed to turn at ~2650 rpm at 75 mph, whether the VCM is on or not. Any thoughts on this?


Sent from AutoGuide.com Free App
 

·
Registered
Joined
·
410 Posts
Discussion Starter · #15 ·
"Retired" Honda master tech here. Sounds like you had a knowledgeable tech who actually took the time to properly diagnose your car. You would not believe the amount of [email protected] techs are at most dealers, usually only a handful that actually know what they are doing.

The chime noise is somewhat normal in those kind of weather conditions. Its a small speaker located in the dash that is about 1" around with a plastic cone. That kind of cold weather would cause it and the diaphragm to shrink and have almost no movement making a "shriek" noise. I use to have a Jaguar that made the most god awful noise when it was really cold too.

VCM has been in Honda V6s now for 10 years and has had complaints since day one...that being said this is a much better version than what debut years ago. You are literally creating a misfire in several cylinders in order to save gas, your going to feel or hear the slightest things at times. Most people don't realize that when you enter VCM mode your engine wants to violently shake which would translate to major vibrations felt throughout the car, but the electric motor-mounts are counteracting the movement. The problem is these motor mounts do wear out rather quickly and don't react well to extreme temperatures. The more miles you put on your V6 the more your going to feel the VCM unfortunately due to the mounts wearing. Now on the flip side, you would see a substantial drop in HWY fuel economy without it.

VCM is activated through switches and oil pressure when your PCM says its within those permitters. Two ways it can easily be deactivated; by disconnecting the oil pressure switch located on your rear bank or de-activating it with the HDS (which is only temporary unless they have installed some new software that I'm not aware of). We use these methods when trying to problem solve issues with the engine, removing the possibility that VCM might be culprit.
The dealer with whom my broker deals (and who services my car) is as good as they come, one of a series of dealerships in the same town owned by the same family--I'd throw a shout out to them, but I don't want to run afoul of board rules! The service manager is pretty cool as well, though maybe has a touch of ADD! (Drives an Accord V6, yet didn't realize that the HomeLink has a light that comes on! Well, when you've got lots of cars coming in...! :confused: ) Fortunately, he knows the technology, as do his shop techs., plus he can work well with someone who can talk the talk enough to be dangerous, but yet doesn't mind a bit! (While having this investigative work done, I also had the car detailed, since the weather went south before I could do it in late October. As might be suspected from the first chime post, I'm OCD about my car! Enough that I was comped an interior detail AND engine detail--that damn car looked BETTER than when I drove it home after taking delivery!! :notworthy Literally so much so that the sales manager wanted to move my car into the showroom to show off until I could get down to get it. :banana: (It's about thirty minutes from work, and I was busier than a one-armed paper hanger in a hurricane!)) I digress!

@RjRacing, some questions for you, if you'd be so kind:

  1. Why is the 6-3 VCM system in the 9th-Gens a better implementation, besides less complexity as compared to the 6-4-3 system in the 8th-Gen Accords (which didn't have "true" VTEC, and a resulting "flat spot" in the torque curve)? (True story: I challenged my Dad, in his 2011 Accord EXL-V6 NAVI, to a safe showdown on a deserted section of straight office park to a 0-50 sprint! Wasn't even close--I spanked him!! These J35s are a mechanical marvel; pray that Honda doesn't sacrifice that V6 goodness on the altar of "green" or CAFE, and leave them for Acuras only, as I can't afford it, and I'll bet lots of the rest of us can't either! :paranoid:)
  2. Should the Active Engine Mount be considered an eventual "maintenance item," just like having $$$ set aside for an eventual timing-belt/water pump swap? Is there only one mount, or several, that would require replacement?
  3. To your knowledge, do any tuners, such as Hondata, offer VCM reprogramming to only activate it at higher speeds, where the VCM operation isn't as obvious? (I'm not ready to pull the plug on the VCM, just to avoid running the risk of voiding warranties or having other undesired side-effects! :paranoid:)

Confirmed it again today--not so bad this morning after the car sat in the garage overnight, but I could feel the VCM with cruise on at 70mph after the car sat outside today. I'll be watching to see at what temperature things "settle down" a bit and aren't as noticeable! (Of course, I'm not sure if this winter will ever end, at least in Ohio!! :thumbsdow As I've stated elsewhere, I picked the car up on March 1st, and was aware of what was happening, but it seemed to go away as the car broke in--and the weather warmed! Duh! :withstupi)

Interesting anecdote about the Jag, BTW!! As stated in that thread, I can live with the noise unless it fails completely, and then I hope to almighty heaven that the beeper is someplace where the entire dash doesn't have to come apart to get to it (with resulting rattles)! :paranoid:

Even with the VCM thing, I'd still buy this car again--best Accord ever! :thmsup:
 

·
Registered
Joined
·
410 Posts
Discussion Starter · #18 ·
Wow, I have an 09 and no issues... just wonder how this happens normally. I am going to post in the summer a cool way to install an engine strut on the cheap. Very similar to my 2000 Toyota. In fact I'll do a side by side.
That'd be good! (I couldn't do it, probably, as a screwdriver in my hand is a deadly weapon! :blush: :withstupi) But I'd still like to see what's involved! O/T, how can one obtain a 9th-Gen printed/PDF Service Manual? (I just like to dig into the nuts and bolts to see how things work, and it seemed to help in dealing with my dealer's service manager, who while, bless his heart, along with his staff, is competent, he is also a little ADD, so if I can "talk the talk" well, and have a touch above a layman's grasp of some of the operational basics of the car's mechanicals, I can help them in troubleshooting or diagnosis. I'm not afraid of getting my hands dirty, and in fact, may obtain a floor jack and stands to do tire rotations and wheel detailing, but I don't have the time, nor the space, to do an oil change!) Helm doesn't seem to have them available. Hell, I'd even buy an HDS dongle and basic laptop software just to have around in case of something weird happening (and I mean something beyond just a basic OBD II scanner)! :thmsup:

Also mods, is it OK to mention a specific dealer in a thread?
 

·
Registered
Joined
·
1,023 Posts
"Retired" Honda master tech here. Sounds like you had a knowledgeable tech who actually took the time to properly diagnose your car. You would not believe the amount of h[email protected] techs are at most dealers, usually only a handful that actually know what they are doing.

The chime noise is somewhat normal in those kind of weather conditions. Its a small speaker located in the dash that is about 1" around with a plastic cone. That kind of cold weather would cause it and the diaphragm to shrink and have almost no movement making a "shriek" noise. I use to have a Jaguar that made the most god awful noise when it was really cold too.

VCM has been in Honda V6s now for 10 years and has had complaints since day one...that being said this is a much better version than what debut years ago. You are literally creating a misfire in several cylinders in order to save gas, your going to feel or hear the slightest things at times. Most people don't realize that when you enter VCM mode your engine wants to violently shake which would translate to major vibrations felt throughout the car, but the electric motor-mounts are counteracting the movement. The problem is these motor mounts do wear out rather quickly and don't react well to extreme temperatures. The more miles you put on your V6 the more your going to feel the VCM unfortunately due to the mounts wearing. Now on the flip side, you would see a substantial drop in HWY fuel economy without it.

VCM is activated through switches and oil pressure when your PCM says its within those permitters. Two ways it can easily be deactivated; by disconnecting the oil pressure switch located on your rear bank or de-activating it with the HDS (which is only temporary unless they have installed some new software that I'm not aware of). We use these methods when trying to problem solve issues with the engine, removing the possibility that VCM might be culprit.
Hmmm. I guess new Acura TLX owners will be experiencing this vibration/judder too since that new V6 engine will be equipped with VCM.
 

·
Registered
Joined
·
410 Posts
Discussion Starter · #20 ·
Hmmm. I guess new Acura TLX owners will be experiencing this vibration/judder to since that new V6 engine will be equipped with VCM.
Interesting thought, but I wonder if the Acuras have more substantial engine mounts and/or structural stuff in that area to minimize the transmission of the noise and vibes to the interior? I haven't trolled around on "acurazine.com" or any of other Acura fan boards to see if they have had similar issues.
 
1 - 20 of 23 Posts
Top