Timing Showing 0 during Idle

Hello,

I have a few questions involving timing and which tables are being used during idle. While observing the "SPARKADV Degr" PID during a start up and idle....my timiing jumps to aprox 13 deg during cranking and then goes to 0 deg while truck is idling...I want to change my timing a little and see if it will stop my headers from getting too hot. I believe the timing is too retarted and I am only able to idle for a few min before the headers get too hot. I'm not exactly sure if this is the correct PID for timing and if so...is it using the Base Spark Table P/N, and if its using this table why it isn't showing me some timing numbers that are remotely close to the table. I will try and post my scan, and tune file. Also...my RPM in the scan tool shows double of what my TAC in my truck reads....i'm sure I must have a setting or unit wrong in my scan tool??

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Thanks guys,

Jordan.

Hi Jordan,

Does it have a strong smell of fuel at the exhaust...?

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Originally Posted by JordanSBC427

Also...my RPM in the scan tool shows double of what my TAC in my truck reads....i'm sure I must have a setting or unit wrong in my scan tool??

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If your ECM thinks your revs are too high, it will pull timing to try to bring them down. Is the RPM in your scantool higher than your desired RPM?

Yes we are getting a strong smell of fuel at the exhaust and lots of water as well. Ok, I thought I logged the desired RPM in the scan file but maybe I didn't...I will double check and do a log with desired rpm if I haven't. Can desired RPM be adjusted or is it derived from a whole wack of different parameters?

Yeah I just checked my log and PID IDLEDES RPM is showing 1180 or so...but my TAC in my dash is showing Aprox 520 or so....Is there an easy way that shows you are running in open or closed loop? I know it will be open loop cause its from a cold start but...would like to see where it says that.

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Originally Posted by JordanSBC427

Can desired RPM be adjusted or is it derived from a whole wack of different parameters?

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Yes, you can adjust it.... {B4603} Desired Idle Speeds

Quote:

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Originally Posted by JordanSBC427

Is there an easy way that shows you are running in open or closed loop? I know it will be open loop cause its from a cold start but...would like to see where it says that.

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Log the pid SAE.FUELSYS

I adjustted the desired idle speeds down a little lower after warm up but nothing too crazy. The RPM still shows higher than desired....any idea what would cause rpm to show much higher than it is actually is?

I added the SAE.FUELSYS and it seems to be working good and showing open/closed loop.

Thanks.