[drumslinger]

As we know, when the ECO light is on, VCM is working, but how many cylinders are shut down? Is there any way of knowing if the engine is running on 3 cylinders or 4?

 

[deuce271]

All I know is that when I have the Trip Computer pulled up and the ECO lights clicks on, there is no noticeable increase in mileage. You would think if 2 or 3 cylinders had kicked off, you'd be able to see that on the Trip Computer.

 

[gmcc]

and all I know is that I was told by two people in the service department at my dealer that teh "Eco" light is not connected to the VCM. They may (and probably do) work at the same time but there is no mechanical link. Maybe someone can verify this.

 

[Army Dad]

As everyone knows I don't know anything, but I believe the 3 cylinders (after they kick in via ECO light) run up to about 60-70 mph and then the 4th kicks in. When I get my car back from the dealer I'll look through the book, I know I've seen it somewhere.

 

[chefmark]

As everyone knows I don't know anything, but I believe the 3 cylinders (after they kick in via ECO light) run up to about 60-70 mph and then the 4th kicks in. When I get my car back from the dealer I'll look through the book, I know I've seen it somewhere.

I agree with Army Dad, he knows nothing.............Just kidding
But I do think he is right, if you are cruising along and the engine is under no real torque then it's on 3, If you ask for some torque to say get up a small hill then it ups to 4 and if you want more torque then all 6 kick in. I think that is what I read.

 

[edubfromktown]

I wish they did something cool like have a 6, 4 or 3 projected on the windshield so you could see how many cyls were active real time 8)

 

[DraEagWol]

I wish they would have a manual overide.. or button to push like... Sport mode, Eco Mode, Super Eco Mode... so we could decide when we want the extra power.. or extra fuel savings..

 

[CMT1]

I was told (by the salesman... most of whom really don't know anything) under 35mph it will shut down to 3 cyl, over 35 it will shut down to 4.

I still can figure out what the eco light does if it's not tied to VCM, perhap it's supposed to indicate when VCM should be on.....

 

[CMT1]

I wish they would have a manual overide.. or button to push like... Sport mode, Eco Mode, Super Eco Mode... so we could decide when we want the extra power.. or extra fuel savings..

With the weight of our car "super eco mode" would mean your friends have to get out and push...

 

[skitour]

Just got back from our 1400 mile round trip out to Ohio. Some observations on the ECO/VCM for what they are worth.
1. The ECO light does not always match the VCM condition. The ECO seems to indicate when the engine is running at it's most efficient state given the demand for power at that moment except when you are accelerating under torq. That said, obviously the ECO light will be on whenever the VCM is running the engine at less than 6 cylinders and there is no demand for torq/acceleration.
2. The long flat cruising zones on I90 across NY using cruise control allowed us to watch how the VCM seems to opperate. At a fixed speed of 70, the VCM will use 3 cylinders to maintain speed on flats and obviously downhill. The VCM will use 4 cylinders to maintin speed on minor elevation changes but only until the cruise control demands more and then the VCM will go to 6 cylinders but that was rare. The ECO light would stay on except when the VCM demanded 6 cylinders. Whenever I wanted more power to pass or to merge, the VCM gave me 6 cylinders and no ECO light.
3. If you can watch the trip computer during this process, you can see the changes in fuel consumption with the VCM change-ups but bear in mind, the VCM wouldn't be adding cylinders if there wasn't a demand so it is not "JUST" the VCM that is changing the real time fuel consumption number, it is demand driven as well.

Hope this makes sense and helps!!!

 

[leek69]

Hope this makes sense and helps!!![/quote]

Does help and thanks for you time reporting what you found