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  • #16
    Originally posted by Claykennedy View Post
    If I have the idle spark advance set at 17 at 1200 rpms should it be at 17 at 900 rpms mine shows 5?
    Just curious, what map are you using? Cause with that amount of vacuum you should be using a race cam map. Also looks like your closed loop is turned off and you’re not getting afr correction. Are you using the idle control?

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    • #17
      Originally posted by akuzaspur View Post

      Just curious, what map are you using? Cause with that amount of vacuum you should be using a race cam map. Also looks like your closed loop is turned off and you’re not getting afr correction. Are you using the idle control?
      I am using the race cam map. Closed loop is on it was just off when I took the pick. Yes I’m trying to use the idle control but with it popping it won’t stay steady.
      Attached Files

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      • #18
        Originally posted by R573CAR View Post
        I have my SBC set at 20* for idle spark. I had it at 15 and it made a big difference when I bumped it up to 20. 5* is way too retarded.
        That’s what I was trying to say. I have the idle spark set at 17 @ 1200rpms but it is only reading 5 at 940.

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        • #19
          Originally posted by Claykennedy View Post

          That’s what I was trying to say. I have the idle spark set at 17 @ 1200rpms but it is only reading 5 at 940.
          Idle spark is not set at a certain RPM point. There is an idle spark set point which as been suggested to be Set around 20*, then the total advance all in by “X” RPM. An example would be 30* @ 2500RPM. Go back to the advanced tuning, spark control and check the settings.

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          • #20
            Is your IAT sensor plugged in ?

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            • #21
              Originally posted by 2700 Cast View Post
              Is your IAT sensor plugged in ?
              Yes. Plugged, unplugged, plugged again. I’ve went through all of the sensors.

              im going to change plugs and wires tonight just because I’m running out of ideas.
              Last edited by Claykennedy; 09-01-2020, 10:43 AM.

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              • #22
                How far do you have the throttle blades open with the set screw? This system also uses timing to maintain idle so it the blades are too far open, it will start pulling timing to maintain set idle. From the looks of your readout, something is confusing the system. I have a 385sbc similar to yours with 20* at idle.

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                • #23
                  Could you post a pic of the screen you're using to set the spark (timing). You can take the pic with the key on, engine off and connected to the ECU.

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                  • #24
                    Originally posted by R573CAR View Post
                    Could you post a pic of the screen you're using to set the spark (timing). You can take the pic with the key on, engine off and connected to the ECU.
                    This screen?
                    Attached Files

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                    • #25
                      Yup. that's the one. It just deepens the mystery of why the idle spark is set to 17* but the gauges pic shows 5*. Way beyond my pay grade. Hopefully a "super mod" can get to the bottom of it.

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                      • #26
                        Originally posted by R573CAR View Post
                        Yup. that's the one. It just deepens the mystery of why the idle spark is set to 17* but the gauges pic shows 5*. Way beyond my pay grade. Hopefully a "super mod" can get to the bottom of it.
                        Yeah. Very odd. And it only pops when it warms up. Runs like crap and will barely idle until then.

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