Who knows how the Chrysler Multi Displacement System (MDS) actually works? I know four cylinders are shut down, but how is this achieved? Do the valves stay open: are they shut: how about fuel and spark? How are the valves controlled anyway? I seem to get a different answer everytime I ask this question. A tech at the dealer said to "just believe". All help appreciated.

 

hehe ok if u really want to know here ya go

The Multi Displacement System selectively deactivates cylinders 1,4,6, and 7, to improve fuel economy. It has two modes of operation : [ul][*]8 cylinders for acceleraton and heavy loads.[*]4 cylinders for cruising and city traffic. [/ul] The main components of the Multi Displacement System are : [ul][*]Unique MDS camshaft.[*]Deactivating roller tappets.[*]4 control valves/solenoids.[*]control valve/solenoid wiring harness.[*]oil temp sensor. [/ul]
OPERATION Cylinder Deactivation [ul][*]Trap an exhaust charge from a normal combustion event[*]Normal combustion event[*]Don't open the exhaust valve[*]Don't open the intake valve[*]Piston is an air spring[*]Cylinders deactivated in firing sequence [/ul] Cylinder Reactivation [ul][*]Open the exhaust valve[*]Empty the cylinder[*]Open the intake valve[*]Normal combustion event[*]Cylinders reactivated in firing sequence [/ul]