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Thread: Cold/Start Open loop fueling correction-2014 ctsv

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    Cold/Start Open loop fueling correction-2014 ctsv

    When i start my car when its cold i noticed that my open loop fueling is a little off. My commanded is approx 2 points richer than what my actual is. So for example commanded was showing 13.2 and my actual was 15.xx. To correct this is it as simple as recording the error while the car is cold and applying that error to the open loop table(s) at the corresponding IVT temps and ECT temps? thanks

  2. #2
    Quote Originally Posted by sgod1100 View Post
    When i start my car when its cold i noticed that my open loop fueling is a little off. My commanded is approx 2 points richer than what my actual is. So for example commanded was showing 13.2 and my actual was 15.xx. To correct this is it as simple as recording the error while the car is cold and applying that error to the open loop table(s) at the corresponding IVT temps and ECT temps? thanks
    The open loop tables you are referring to change the commanded not the actual. You need to change your MAF and or VVE tables to match the commanded. Does it match once it is warm and in OL?

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    Quote Originally Posted by asteggall View Post
    The open loop tables you are referring to change the commanded not the actual. You need to change your MAF and or VVE tables to match the commanded. Does it match once it is warm and in OL?
    Yeah, once it's warmed up it's spot on. It's only on cold start up. That's where i'm kind of confused

  4. #4
    Quote Originally Posted by sgod1100 View Post
    Yeah, once it's warmed up it's spot on. It's only on cold start up. That's where i'm kind of confused
    Just to confirm, but when it is warmed up and spot on it is in OL ( trims reading 0) ?

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    Quote Originally Posted by asteggall View Post
    Just to confirm, but when it is warmed up and spot on it is in OL ( trims reading 0) ?
    Yes, it is in OL...i just went back to CL a few days ago to confirm that my WB is indeed accurate and the trims are +/-2% which i feel is good to go

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    Watching this as i also have the same issue, running OL SD.

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    Yeah, I don't understand why i can't log my IVT temp along with ECT and record the fueling error and apply it to the open loop table. Basically the same concept as doing WOT afr error process. So I wouldn't be touching the MAF or VVE during this process. Does this sounds completely stupid? lol

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    Quote Originally Posted by sgod1100 View Post
    Yeah, I don't understand why i can't log my IVT temp along with ECT and record the fueling error and apply it to the open loop table. Basically the same concept as doing WOT afr error process. So I wouldn't be touching the MAF or VVE during this process. Does this sounds completely stupid? lol
    I think i'll just try this and report back to you guys..

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    could raise your pulse width adder in the injector temp offset table at the lower temps (<=95F cell, give or take)

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    Quote Originally Posted by RobZL1 View Post
    could raise your pulse width adder in the injector temp offset table at the lower temps (<=95F cell, give or take)
    Is that the injector offset vs injector temp table in the "general" tab?

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    log of the fueling being way off of commanded along with my tune
    Attached Files Attached Files

  12. #12
    Quote Originally Posted by sgod1100 View Post
    Yeah, I don't understand why i can't log my IVT temp along with ECT and record the fueling error and apply it to the open loop table. Basically the same concept as doing WOT afr error process. So I wouldn't be touching the MAF or VVE during this process. Does this sounds completely stupid? lol
    Because the tables under the open loop/base table (12435 and 12441) Control the commanded open loop EQ. You don't want to match commanded to the WB. you want to match the WB to the commanded.

    Quote Originally Posted by sgod1100 View Post
    Is that the injector offset vs injector temp table in the "general" tab?
    Yes

    Quote Originally Posted by sgod1100 View Post
    Yes, it is in OL...i just went back to CL a few days ago to confirm that my WB is indeed accurate and the trims are +/-2% which i feel is good to go
    Well it's not in full OL. If you look at the log it is OL and not far off from commanded till 30 seconds in. Then you will see you STFT come alive and start to pulling fuel to bring it back to lambda. Now your LTFT are disabled till the ECT reaches 133, but the STFT are active.

    Try commanding STFT and LTFT off in the controls section of the scanner and see what it does.

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    Quote Originally Posted by asteggall View Post
    Because the tables under the open loop/base table (12435 and 12441) Control the commanded open loop EQ. You don't want to match commanded to the WB. you want to match the WB to the commanded.



    Yes



    Well it's not in full OL. If you look at the log it is OL and not far off from commanded till 30 seconds in. Then you will see you STFT come alive and start to pulling fuel to bring it back to lambda. Now your LTFT are disabled till the ECT reaches 133, but the STFT are active.

    Try commanding STFT and LTFT off in the controls section of the scanner and see what it does.
    Exactly i noticed that as well, that it was running pretty much stoic when the commanded was much richer. I'll try and turn the STFT and LTFT off to see what that does

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    how can the STFT be active while in OL? Also my "Fuel system status" says OL as well
    Last edited by sgod1100; 03-28-2019 at 05:19 PM.

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    sooooo. even when i turn off closed loop via the scanner it's still running 5 to 6% lean....sooo any ideas?

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    Whats the best way to adjust the OL tables so the WB matches the commanded? Would I adjust the IVT gain table? There's got to be some stupid table that i'm not seeing to keep the STFT from turning on so soon

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    I think i may try and set the "o2 readiness" to 284 at the lower ect temps. Maybe that will prevent the STFT from starting so early

  18. #18
    Quote Originally Posted by sgod1100 View Post
    I think i may try and set the "o2 readiness" to 284 at the lower ect temps. Maybe that will prevent the STFT from starting so early
    That's how I disable STFT, just set the whole table to 284.
    2010 GXP Maloo ute, LS3, 6L80E.
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    Quote Originally Posted by Xjas View Post
    That's how I disable STFT, just set the whole table to 284.
    I still want to use STFT, but not during cold start/ OL...i'll try to see what happens. thanks

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    Well, Xjas was right. I set O2 readiness temp to 133 F across the board which is when i have the LTFT kick in and i got absolutely no influence from the STFT while in OL. As soon as 133 F hit the STFT started working. SOOOO, now i think i will alter the IVT gain table slightly so I can get rid of the small amount of error i have in fueling during cold idle
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