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Discussion Starter · #1 ·
..just wondering if anyone knows at what RPM does the MDS not kick in on the highway??? It can't be activated cruising at 100mph is it?? If it's a matter of a few MPH's, it would be worth knowing for fuel economy.
 

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hemipower said:
..just wondering if anyone knows at what RPM does the MDS not kick in on the highway??? It can't be activated cruising at 100mph is it?? If it's a matter of a few MPH's, it would be worth knowing for fuel economy.
I would like to know at what MPH this works as well. My commute each day to work puts me on a highway where I usually do 85+ (far west outside Houston) and my average MPG for a tank has rarely been above 17.
 

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If only we had a light like the 05 Odyssey, this would be just one more electrical thing to not work which is why I think they left it out.
 

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II kings 9:20 said:
If only we had a light like the 05 Odyssey, this would be just one more electrical thing to not work which is why I think they left it out.
That, and I am not sure how long it would be before I got really pissed with a light on my dash constantly going on and off depending on engine load.
 

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Discussion Starter · #7 ·
It isn't on at idle, its running on all 8 cylinders...that I read in the Motor Trend mag. It just didn't say anything about what RPM it kicks on...
 

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I've previously thought about wiring up a temporary LED for testing purposes just to answer these type questions. It shouldn't be difficult as there is a relay driving the solenoids that activate MDS. You could tap into that to drive an LED.
 

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I read someplace that it works above 40 MPH and only when a low percentage of power is needed to maintain speed. If you can maintain 100 MPH at that low power level I think it would work.
 

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Discussion Starter · #10 ·
...interesting. I would have thought once it reached a certain RPM, it wouldn't activate because of the higher RPM's. the higher the RPM's, the more the engine is working right?? would be nice to know for sure to save some fuel....although if I stopped hammering it at every light that would probably help as well!!!
 

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According to this article from popular mechanics, "the minimum and maximum oil pressure limits for cylinder deactivation and reactivation were established at 75 psi and 18 psi".

They also have a graph showing the cycling of the MDS when they drive to home depot.
 

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C-Man, I think those guy's missed it. 18 and 75 psi are the mininum and max oil pressures of the engine. Not the pressures that activate or deactivate the lifters. I think the relief valve in the oil pump is set to 75 psi and the weight of the oil would set the min. pressure. That's my take on it, but I haven't studied the engine. Correct me if I'm wrong. As if you guy's wouldn't :)

Dixie
 

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C-Man said:
According to this article from popular mechanics, "the minimum and maximum oil pressure limits for cylinder deactivation and reactivation were established at 75 psi and 18 psi".

They also have a graph showing the cycling of the MDS when they drive to home depot.
Good article, thanks!
 

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cant be RPM

It cant be related to RPM- Road speed/wheel speed would be my guess, along with load factored in.

Jay
 
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