Hunting

Discussion in 'Dodge 2nd Gen Cummins 5.9 (24v)' started by grouchrc, Jul 13, 2006.

  1. grouchrc

    grouchrc Active Member

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    When not towing at highway speeds on cruise control i notice a very small hunt, speed varying up and down about 1/4 mph. When I install SMARTY on timing only for mileage I get a 1 mph hunt.
    I know the cruise control is controlled by the PCM. IS there anyway this can be reprogramed to eliminate the hunt?
    When i used to install a CC on a car, J>C> Whitney sells them, it had a selector for 4, 6, or 8 cyl to control the sensitivity. If they could do that 20 years ago they should be able to do it now.
     
  2. Diesel Nut

    Diesel Nut Well-Known Member

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    I seem to remember reading something on TDR a ways back about slightly pinching off the vaccume line for the Cruise Control actuator becasue of it being to sensitive and that would slow down the responsiveness and smooth it out. Worth a shot.
     
  3. grouchrc

    grouchrc Active Member

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    Someone suggested a needlevalve in the line.
    Sililar to what you suggested. However, the line is hard plastic except for the rubber slipconnection at each end. Will have to find something I can put in the line.
     
  4. RJF's Red Cummins

    RJF's Red Cummins TRC Staff Moderator

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    IIRC, 2002's have electronic cruise control and do not use vaccuum like older models. The trick with the vaccuum line was to stick a piece of a straw in it, something to limit the flow through the line.

    I don't know why a 2002 would want to "hunt" on cruise.
     
  5. grouchrc

    grouchrc Active Member

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    I don't know why it hunts either. My 2002 has the vacuum servo for the CC.
    Will try to reduce the flow somehow.
     
  6. rocknbronco

    rocknbronco Well-Known Member

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    Has it been hunting all the time or is it something more recent?Your might want to get it looked over once by the folks at Dodge.
     
  7. grouchrc

    grouchrc Active Member

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    It always had a very small hunt but not enough to be a problem. The addition of SMARTY made it worse. I haven't tried towing yet.
     
  8. grouchrc

    grouchrc Active Member

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    At Shucks the other day I found a 3/16 straight barbed fitting that had a builtin orfice-very small. It seemed to help but I might try to make it smaller.
    Easier to install than a needle valve.
     

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