XPost: rec.autos.tech, alt.home.repair   
   From: xenolith@optusnet.com.au   
      
   On 24/4/2023 2:24 pm, Michael wrote:   
   > On Mon, 24 Apr 2023 14:10:13 +1000, Xeno wrote:   
   >   
   >>> Does the PCM shut down the spark or the fuel to that misfiring cylinder?   
   >>   
   >> It will definitely shut off the fuel - if nothing else. If you have fuel   
   >> but no spark you will be flooding the cat with raw fuel. That's bad.   
   >   
   > I wonder what it does because it's impossible to shut off the fuel since   
   > there is only one intake manifold and the injectors inject fuel into it   
   > just like a carburetor would have, only a bit closer to the cylinders.   
   >   
   > If they shut down the fuel there will ALWAYS be fuel getting into the   
   > cylinders, but maybe the baffles are designed that one injector "mostly"   
   > injects into one cylinder for cars that aren't direct injected (which is   
   > most cars that are NOT direct fuel injected).   
      
   Should mention, I suppose, that it only apples to sequential injection   
   with cylinder specific misfire monitors, V8 & V6 engines typically. Gang   
   fired injection systems just might not run so well with *half* the   
   cylinders getting no injection pulses.  😉   
   For the rest it's goodbye to the cat if the vehicle continues to be   
   driven, or it goes into some form of severe limp mode and that pretty   
   much forces rectification of the issue.   
      
   --   
   Xeno   
      
      
   Nothing astonishes Noddy so much as common sense and plain dealing.   
          (with apologies to Ralph Waldo Emerson)   
      
   --- SoupGate-Win32 v1.05   
    * Origin: you cannot sedate... all the things you hate (1:229/2)