Is 4-cylinder mode vibration/humming normal for VCM?

[Robotaz]

Overall, i love my new Accord coupe. BUT, I took it on a roadtrip yesterday and everytime I started going up a hill on the interstate it would vibrate and hum to the point of being very irritating due to switching from 3-cylinder mode to 4-cylinder mode. If I pushed the accelerator down to get all 6 to kick in it goes away. Additionally, when i go over the hill and go level or downhill the torque converter does this very irritating lock/unlock routine that causes a surging feeling. I will sell the car at a loss before I deal with this crap every time I get it on the highway. Is this "normal" for VCM or is there a problem? If I can't get it fixed I will have to sell it because my fiance wants to kill me now for buying such a nice car that is so annoying to drive. It will have to go just to keep from hearing the complaining, plus it annoys me, too. Any advice?

[northcoast]

I can't say that I've had that problem with my V6 Sedan...

Just curious, does it happen with cruise control on? It would be an interesting test to see if the car respondes the same both with and without cruise control. It would at least remove the human factor, and, it would also insure that you could duplicate the problem with the dealer in the car...

[mhadden]

Originally Posted by Robotaz

...Additionally, when i go over the hill and go level or downhill the torque converter does this very irritating lock/unlock routine that causes a surging feeling...

This is normal. It's called Grade-logic control. Don't know about the rest, though.

[walhaddi]

everything you said happens to me and it is normal for that type of engine with those oprions (VCM). I first thought the tranny had something wrong with it, but I watched it more and the humming and vibrations only happens when the ECO light goes on or less then a second before it goes on. I am ok with it though (I am saying I feel ok since there is nothing wrong with the car). Just deal with it and if not then sell it. I thought about selling it myself, but too muxh $$ will be lost. Plus, the car looks nice.
If I can do it all over, I will get a new TL and paint the grill off course.

[Robotaz]

Originally Posted by northcoast

I can't say that I've had that problem with my V6 Sedan...

Just curious, does it happen with cruise control on? It would be an interesting test to see if the car respondes the same both with and without cruise control. It would at least remove the human factor, and, it would also insure that you could duplicate the problem with the dealer in the car...

Strange you ask, because I can't get it to do the same in cruise. But I think that is because I'm just pushing it down slightly more, the gas that is, than the computer wants to for economy purposes. If you go faster in cruise it does not do it as badly. I think it's strained when it does it. With more speed and power built up due to increased RPMs it diminishes. I was travelling about 72 mph on pretty steep hills relative to most places. I'll try it slower next time and see what happens. I am glad to hear that this particular car is probably not broken anyway. Thanks for the replies.

[hawkwind]

I don't think its normal. My VCM is very smooth. Once you start going uphill it should automatically go to 6cyl not 4. Whenever I reach any kind of incline there is more load so my car always switches to 6cyl mode. Never felt any vibrations or hum ever. As far as I am concerned it is smooth as silk. I don't even notice it when it switches from 3-4-6.

[elp_jc]

Boy, am I glad the 6MT doesn't have it; it'd have been a deal breaker for me. Not worth the 1 or 2 mpg difference AT ALL.

What I don't understand is why the hell Honda didn't put a freaking button to deactivate it. It's not like ABS, VSC, or any other 'safety' feature; it's simply a fuel mileage one, that it's not that 'transparent' after all.

Did you check your manual to see if there's only one fuse for VCM? If that's the case, you're in luck. Just remove it, like many of us removed the one for DRLs. Good luck man.
JC

[hawkwind]

Although as I said in my other post that I don't have the problems that the OP has. I wish I got the 6MT instead. In the 25 years of driving I have never owned an AT. This is the first. I got the AT because I was getting a little tired of shifting all the time and thought I could use a change. Also the wife doesn't drive stick and I do about 70% highway driving so the MPG savings for me would be more than the 1 MPG. Now I wish that I did get the MT. Not that I have an iissue with VCM but I didn't realize at the time that the VTEC was different on both engines. I did a ton of research and looked at all the reviews and even the Honda site and noone ever mentioned the performance difference between the two. Dual profile cams, lighter manifold, performance intake and exhaust, etc. This is something the sales guy should have told me since he knew I was heavily debating MT vs. AT. Plus I am now missing the stick more than I thought.

But having said that I am not too disapointed with the AT. Hell if I am on the highway going 130KM/hr (80m/hr) (kind of the standard speed on Toronto highways though not the legal speed) I can still put the pedal down and it will fly. Thats all I really care about.

Ask the sales guy what hit I would take to trade in and get the MT and it was about $9,000. Too big of a hit for me.

[catbert430]

I found the VCM irritating when I first got the car.
After 2,000 or so miles, it got a lot smoother.
That - probably combined with my getting used to it - really made a difference.
I don't even notice it any more except for the green ECO light.

[mhadden]

Sometimes I think Honda should have stuck with the previous 3.0L V6 instead of boring it our another 1.2 litre. Although HP and torque probably wouldn't have increased much, the mpg's could've stayed similar. But don't get me wrong, I love my 6MT and my 3.5 non-VCM engine