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spark plugs

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  • spark plugs

    have 2008 impala dedicated cng with 3.9l what gapped should spark plugs be? for cng to run best

  • #2
    ?Brand of CNG system ECM?
    ?What plugs were installed originally on that system?
    '13 Chev Silverado 2500 Ext Cab Factory Bi-Fuel
    '08 Green Tea Metallic GX
    FMQ-2-36 Fueler


    • #3
      i kn conversation was done by tulsa gas technolgies ill look underhood at what brand tommorow idk bout the plugs cause wheni changed them i didnt see what brand they was..


      • #4
        its natural drive


        • #5
          Oh, I used to produce those

          We used to recommend:
          * Spark Plugs: AC Delco Iridium tip
          * Gap: .042-.046"
          Last edited by John Mitton; 12-20-2017, 01:12 PM.


          • #6
            John Mitton thanks you ive had this impala for a year now and this my first cng vehicle when i first got it i had hard start when 50* or colder soo i put injectors and new sparkplugs and spark plug wires but still have little bit of hardstart when cold soo ive just dealt with it thinking maybe its just how cng vehicles start in the cold i dont know what the sparkplug gap was orignally but i put new plugs in and they was gapped at the factory specs soo .060 soo if i regapped them at .042 will that help cold starts?