Weird idle problem (continuation from the troubleshooting forum)
Welcome to the Cadillac CTS-V Forum at CTSVOwners.com.
Results 1 to 13 of 13
  1. #1
    Active Member
    Join Date
    Oct 2017
    Posts
    134

    Weird idle problem (continuation from the troubleshooting forum)

    At slight throttle, the car will idle up, then drop rpms. In the log, from steady idle, I'll move the pedal to ~23%. Throttle responds, but after a couple of seconds, will start to fall, even though I'm keeping the pedal at ~23%. Commanded throttle drops for no reason that I can determine. WTF???
    Attached Files Attached Files
    Last edited by chibajoe; 11-06-2019 at 09:51 AM.

  2. #2
    Active Member
    Join Date
    Jan 2017
    Location
    Greensboro NC
    Posts
    2,727
    Would be interesting to see the throttle blade in action...if its staying open with your foot still on or not. Weird indeed.
    Build Thread for the Madallac

    Open and Shut - A Tranny Story (TR6060 Teardown and Rebuild)

    JRi Coilovers

    ’09 Sedan Black on Black Recaros 6MT
    Forged HED LSA 10:1 GP 2.5 Ported LSA Heads/TVS1900 Johnson 2110s 2.70/9.55 Pulleys D3 Intake Lid Spacer SW 2”/Catless/Magnaflow Resonators/Corsa Spt DIY Flex Setup ID1300Xs DW300Cs + Walbro 297 Map Ref Aux
    Low Mount D3 HX and Pump -10 Setrab Oil Cooler Diff Cooler Lowered on JRIs Subframe Reinforcement Front and Rear D3 Sway Bars Core Shifter Mantic Twin Disc Clutch Swapped/Widened Sedan Wheels

  3. #3
    Active Member
    Join Date
    Oct 2017
    Posts
    134
    If I command more throttle (like 28%), it will respond and stay, so this behavior only happens between ~22-26% throttle, and it is pretty consistent and repeatable. Already replaced the throttle body/cleaned MAF/new air filter, with no change in behavior.

  4. Remove Advertisements
    CTSVOwners.com
    Advertisements
     

  5. #4
    Active Member
    Join Date
    Nov 2013
    Location
    Watauga TX
    Posts
    3,071
    Might check the peddle output with a meter and see if it is falling off.
    2013 TG Sedan

    ID1050x's, 2.4 griptech/8.66 lower, GP 2.5 cam, AEM drop in pumps, custom added Walbro 450 pump, DSX flex fuel sensor, DMS Auxiliary Fuel Filter, Track Attack HX, CWA50 pump, ZL1 Lid. 90mm TB, Kooks catless headers, Airaid with green filter, Moroso catch can, AFR500v2 wideband, tuned by Pat G/Me.


    2011 BDT Sedan
    ID850's, 2.4 upper, Track Attack HX, Varimax pump, ZL1 Lid, Texas Speed headers, Airaid with green filter, Moroso catch can, LPE tank, PLX wideband, tuned by Pat G.

  6. #5
    Active Member
    Join Date
    Oct 2017
    Posts
    134
    Quote Originally Posted by ASteggall View Post
    Might check the peddle output with a meter and see if it is falling off.
    Thought about that, but if that was the case, throttle position would drop in the log, but it doesn't.

  7. #6
    Active Member
    Join Date
    Jan 2017
    Location
    Greensboro NC
    Posts
    2,727
    Quote Originally Posted by chibajoe View Post
    Thought about that, but if that was the case, throttle position would drop in the log, but it doesn't.
    TPS and accelerator position are two different channels Cheebs
    Build Thread for the Madallac

    Open and Shut - A Tranny Story (TR6060 Teardown and Rebuild)

    JRi Coilovers

    ’09 Sedan Black on Black Recaros 6MT
    Forged HED LSA 10:1 GP 2.5 Ported LSA Heads/TVS1900 Johnson 2110s 2.70/9.55 Pulleys D3 Intake Lid Spacer SW 2”/Catless/Magnaflow Resonators/Corsa Spt DIY Flex Setup ID1300Xs DW300Cs + Walbro 297 Map Ref Aux
    Low Mount D3 HX and Pump -10 Setrab Oil Cooler Diff Cooler Lowered on JRIs Subframe Reinforcement Front and Rear D3 Sway Bars Core Shifter Mantic Twin Disc Clutch Swapped/Widened Sedan Wheels

  8. #7
    Active Member
    Join Date
    Nov 2013
    Location
    Watauga TX
    Posts
    3,071
    Something is off with your PIDs you are logging. At idle your pedal PID should read 0.


    Weird idle problem (continuation from the troubleshooting forum)-capture.png
    Last edited by ASteggall; 11-07-2019 at 12:20 PM.
    2013 TG Sedan

    ID1050x's, 2.4 griptech/8.66 lower, GP 2.5 cam, AEM drop in pumps, custom added Walbro 450 pump, DSX flex fuel sensor, DMS Auxiliary Fuel Filter, Track Attack HX, CWA50 pump, ZL1 Lid. 90mm TB, Kooks catless headers, Airaid with green filter, Moroso catch can, AFR500v2 wideband, tuned by Pat G/Me.


    2011 BDT Sedan
    ID850's, 2.4 upper, Track Attack HX, Varimax pump, ZL1 Lid, Texas Speed headers, Airaid with green filter, Moroso catch can, LPE tank, PLX wideband, tuned by Pat G.

  9. #8
    Active Member
    Join Date
    Oct 2017
    Posts
    134
    Quote Originally Posted by adam112 View Post
    TPS and accelerator position are two different channels Cheebs
    Sorry, meant pedal position, not throttle position.

    Quote Originally Posted by ASteggall View Post
    Something is off with your PIDs you are logging. At idle your pedal PID should read 0.


    Click image for larger version. 

Name:	Capture.PNG 
Views:	4 
Size:	25.7 KB 
ID:	139242
    Pedal position SAE is % of pedal sensor voltage, I believe, so 0V=0%.
    Last edited by chibajoe; 11-07-2019 at 02:20 PM.

  10. #9
    Active Member
    Join Date
    Nov 2013
    Location
    Watauga TX
    Posts
    3,071
    Quote Originally Posted by chibajoe View Post
    Sorry, meant pedal position, not throttle position.



    Pedal position SAE is % of pedal sensor voltage, I believe, so 0V=0%.
    But in your whole log your pedal % never goes to 0. Did you always have your foot on the gas?
    2013 TG Sedan

    ID1050x's, 2.4 griptech/8.66 lower, GP 2.5 cam, AEM drop in pumps, custom added Walbro 450 pump, DSX flex fuel sensor, DMS Auxiliary Fuel Filter, Track Attack HX, CWA50 pump, ZL1 Lid. 90mm TB, Kooks catless headers, Airaid with green filter, Moroso catch can, AFR500v2 wideband, tuned by Pat G/Me.


    2011 BDT Sedan
    ID850's, 2.4 upper, Track Attack HX, Varimax pump, ZL1 Lid, Texas Speed headers, Airaid with green filter, Moroso catch can, LPE tank, PLX wideband, tuned by Pat G.

  11. #10
    Active Member
    Join Date
    Nov 2013
    Location
    Watauga TX
    Posts
    3,071
    What are your mods? Just looked at the tune, why is your ETC scalar at 4936? Stock is 5060.
    2013 TG Sedan

    ID1050x's, 2.4 griptech/8.66 lower, GP 2.5 cam, AEM drop in pumps, custom added Walbro 450 pump, DSX flex fuel sensor, DMS Auxiliary Fuel Filter, Track Attack HX, CWA50 pump, ZL1 Lid. 90mm TB, Kooks catless headers, Airaid with green filter, Moroso catch can, AFR500v2 wideband, tuned by Pat G/Me.


    2011 BDT Sedan
    ID850's, 2.4 upper, Track Attack HX, Varimax pump, ZL1 Lid, Texas Speed headers, Airaid with green filter, Moroso catch can, LPE tank, PLX wideband, tuned by Pat G.

  12. #11
    Active Member
    Join Date
    Oct 2017
    Posts
    134
    Quote Originally Posted by ASteggall View Post
    What are your mods? Just looked at the tune, why is your ETC scalar at 4936? Stock is 5060.
    I was running a 90mm TB, but put the stock one back on while trying to troubleshoot the problem. ETC scalar was 5936; I knew stock was around 5K so I just subtracted 1K (was running late for work, didn't have time to look it up). LS9 cam, headers, pulley, 850lb injectors, nothing crazy.

  13. #12
    Active Member
    Join Date
    Nov 2013
    Location
    Watauga TX
    Posts
    3,071
    I would start with a stock tune and just change the injector info and see if it does it. A LS9 cam is not that aggressive so it should run at 23% throttle no problem.
    2013 TG Sedan

    ID1050x's, 2.4 griptech/8.66 lower, GP 2.5 cam, AEM drop in pumps, custom added Walbro 450 pump, DSX flex fuel sensor, DMS Auxiliary Fuel Filter, Track Attack HX, CWA50 pump, ZL1 Lid. 90mm TB, Kooks catless headers, Airaid with green filter, Moroso catch can, AFR500v2 wideband, tuned by Pat G/Me.


    2011 BDT Sedan
    ID850's, 2.4 upper, Track Attack HX, Varimax pump, ZL1 Lid, Texas Speed headers, Airaid with green filter, Moroso catch can, LPE tank, PLX wideband, tuned by Pat G.

  14. #13
    Active Member
    Join Date
    Oct 2017
    Posts
    134
    Quote Originally Posted by ASteggall View Post
    I would start with a stock tune and just change the injector info and see if it does it. A LS9 cam is not that aggressive so it should run at 23% throttle no problem.
    And, just like that, the problem seems to have fixed itself. Did a throttle relearn after I swapped out the throttle body, then did another one after I swapped the 90mm back in, and all of a sudden, no problems. Sigh, I'm just going to keep my fingers crossed that it doesn't happen again. Hopefully it's not the throttle body going bad somehow.


 

Sponsored Links

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  

Thread Information

Users Browsing this Thread

There are currently 1 users browsing this thread. (0 members and 1 guests)

     

Back to top