MDS activation during engine idle? / 2023 Ram 5.7 eTorque / does anyone know if the 5.7s are designed to run on 4 cylinders when the engine is idling?

[HemiSue]

Please see above

 

[Wild one]

Please see above

No mds during idle.If it's going into 4 cylinder mode while idling,you have issues.

 

[mikeru]

You have etorque so the engine should shut off when conditions are met for stop/start operation when the truck is stopped and the engine is idling. But as mentioned, it should never run on 4 cylinders when idling.

 

[HemiSue]

thanks to both for the responses. I actually turn off the start stop feature Every time I turn on the engine, I suspect it affects the longevity of the engine. I have no reason to think that’s occurring when idling I was just curious. Seems like that would be the most opportune time to use the MDS and save fuel, but I suppose there is a good reason that it is not used while idling?

 

[mikeru]

thanks to both for the responses. I actually turn off the start stop feature Every time I turn on the engine, I suspect it affects the longevity of the engine. I have no reason to think that’s occurring when idling I was just curious. Seems like that would be the most opportune time to use the MDS and save fuel, but I suppose there is a good reason that it is not used while idling?

At the risk of starting another discusison on that, school is still out on whether turning MDS off affects engine longevity. But I think there is a general consensus that leaving it on does not hurt your engine. Although I'm not sure there's anything more than anecdotal evidence supporting that as well.

As far as MDS being active while idling, You would have idling issues when it's only running on four cylinders.

 

[Wild one]

thanks to both for the responses. I actually turn off the start stop feature Every time I turn on the engine, I suspect it affects the longevity of the engine. I have no reason to think that’s occurring when idling I was just curious. Seems like that would be the most opportune time to use the MDS and save fuel, but I suppose there is a good reason that it is not used while idling?

Oil pressure at idle would fall through the bottom,if it shut down 4 cylinders while idling, it takes oil pressure to activate the mds.
As Mike stated above,it would need programming to kick the idle speed up if it only had 4 cylinders working at idle,otherwise it'd die.

 

[HemiSue]

Excellent answers….thanks much