Results 1 to 15 of 15

Thread: Possible bad E38 ECM

  1. 04-03-2017 #1
    Brownvette
    Brownvette is offline
    Tuner in Training
    Join Date
    Jan 2017
    Location
    South Carolina
    Posts
    15

    Possible bad E38 ECM

    Hi all,
    I'm rather new to the forum and I've been having alot of trouble out of my 2006 Corvette so i thought I would post a few questions here. A while back i had to the crank and stall condtion, chased my tail around and turned out it was VATS, so i disabled it Via HPTuners. After i removed VATS i cranked it and now It has an idle surge, the MIL will come on and the rpms will surge up and then back down to around 900 rpm. I've tried capturing the DTC with no success, i've enabled just about every possible MIL and set it to "first error and ses light". I've even unplugged to MAF to see if it would set the DTC, no success. Even commands such as clutch interlock disable doesnt work, and It wont respond to manually turning the fan on and off through VCM. Is this possibly a bad ECM? Almost forgot, build is a supercharged Iron 408, 243 (Ls2) heads, 2006 Corvette M6

    As i said, I'm new so ill try to post the tune and the scan logs i have, but the scan stops logging as soon as the MIL comes on and right before it surges, like the ECM just stops communicating for a spit second. Would some of the pro's mind looking at the tune and see if they see anything crazy? I didnt do the tune, had it tune a while back by a professional. Thanks!

    https://www.youtube.com/watch?v=rsKJG-FDl5Q
    Attached Files Attached Files
    Last edited by Brownvette; 04-03-2017 at 09:58 PM.
    Reply With Quote Reply With Quote
  2. 04-04-2017 #2
    10_SS
    10_SS is offline
    Senior Tuner 10_SS's Avatar
    Join Date
    Mar 2012
    Location
    Detroit, MI
    Posts
    1,320
    Quote Originally Posted by Brownvette View Post
    Hi all,
    I'm rather new to the forum and I've been having alot of trouble out of my 2006 Corvette so i thought I would post a few questions here. A while back i had to the crank and stall condtion, chased my tail around and turned out it was VATS, so i disabled it Via HPTuners. After i removed VATS i cranked it and now It has an idle surge, the MIL will come on and the rpms will surge up and then back down to around 900 rpm. I've tried capturing the DTC with no success, i've enabled just about every possible MIL and set it to "first error and ses light". I've even unplugged to MAF to see if it would set the DTC, no success. Even commands such as clutch interlock disable doesnt work, and It wont respond to manually turning the fan on and off through VCM. Is this possibly a bad ECM? Almost forgot, build is a supercharged Iron 408, 243 (Ls2) heads, 2006 Corvette M6

    As i said, I'm new so ill try to post the tune and the scan logs i have, but the scan stops logging as soon as the MIL comes on and right before it surges, like the ECM just stops communicating for a spit second. Would some of the pro's mind looking at the tune and see if they see anything crazy? I didnt do the tune, had it tune a while back by a professional. Thanks!

    https://www.youtube.com/watch?v=rsKJG-FDl5Q
    Some of these problems remind me of when I bought an Ebay spare ECU, wrote entire tune to it, then I also had problems with VATS not working, and the clutch interlock not working, and some other things. I never did get it working right, so I just quit using it. HPT does not read/write the entire contents of the ECU.

    Then recently, I was playing with an older OS than the one I'm using now (one that was 2bar updateable before my OEM tune was 2bar updateable), I put all of my settings into it and flashed my stock ECU.... then the throttle woudnt work 100% the same... when I would attempt to hold say 1000rpm with the pedal, after 1-3seconds the ECU would pull RPM back down to desired Idle for me.

    So is this your OEM ECU and OEM OS?
    2010 Camaro LS3 (E38 ECU - Spark only). MS3X running complete RTT fuel control (wideband).
    Whipple 2.9L, 3.875" Pulley, kit injectors, supplied MSD Boost-A-Pump, stock pump
    LG Motorsports 1 7/8" Headers - No Cats, stock mid pipe with JBA Axle Back
    ZL1 Wheels/Tires
    Reply With Quote Reply With Quote
  3. 04-04-2017 #3
    Brownvette
    Brownvette is offline
    Tuner in Training
    Join Date
    Jan 2017
    Location
    South Carolina
    Posts
    15
    Yes everything is OEM, which is what I cant understand why VATS would all of a sudden stop working on a pretty much stock/oem car, other than the engine swap, which is just an Iron LS2 (Ly6) block. I did order another ECM from ebay just to try and flash. I 'll be uploading some more logs as well. I did see on one log where i had 23 misfires....lol no bueno. Could my car for some reason need a crank relearn? I doesnt have any issues cranking/starting. Just the idle surge and I cant really touch the throttle or it wants to shut down...I tried to drive it around the block and it kept wanting to die anytime i gave it any gas.
    Reply With Quote Reply With Quote
  4. 04-04-2017 #4
    Brownvette
    Brownvette is offline
    Tuner in Training
    Join Date
    Jan 2017
    Location
    South Carolina
    Posts
    15
    Some more logs from the other day
    april_am_log_1.hpl
    april_am_log_2.hpl


    Reply With Quote Reply With Quote
  5. 04-04-2017 #5
    Brownvette
    Brownvette is offline
    Tuner in Training
    Join Date
    Jan 2017
    Location
    South Carolina
    Posts
    15
    The many misfires that were counted during a log make me wonder if it possibly needs a crank relearn, but i have no starting issues and I OHMd the crank sensor itself, all good. Would it screw anything up if i had to stop in the middle of a crank relearn? I'm kind of afraid to run the procedure with all the misfires, whats wierd it I dont really feel any misfires unless i try to drive it or rev it a little, it does back fire, but i assume thats bc shes running pig rich.
    Reply With Quote Reply With Quote
  6. 04-04-2017 #6
    GHuggins
    GHuggins is offline
    Tuning Addict
    Join Date
    Jan 2015
    Location
    Franklin, NC / Gainesville, Ga
    Posts
    6,815
    Hmmm. Now for some more questions... Was the crank welded on? If it was - was it ever demagnetized? Did it have the backfires since newly built? You say it was "pro tuned" - was it running right then? Did all of this rough running just recently start?
    2010 Vette Stock Bottom LS3 - LS2 APS Twin Turbo Kit, Trick Flow Heads and Custom Cam - 12psi - 714rwhp and 820rwtq / 100hp Nitrous Shot starting at 3000 rpms - 948rwhp and 1044rwtq still on 93
    2011 Vette Cam Only Internal Mod in stock LS3 -- YSI @ 18psi - 811rwhp on 93 / 926rwhp on E60 & 1008rwhp with a 50 shot of nitrous all through a 6L80

    ~Greg Huggins~
    Remote Tuning Available at gh[email protected]
    Mobile Tuning Available for North Georgia and WNC
    Reply With Quote Reply With Quote
  7. 04-04-2017 #7
    Brownvette
    Brownvette is offline
    Tuner in Training
    Join Date
    Jan 2017
    Location
    South Carolina
    Posts
    15
    Quote Originally Posted by GHuggins View Post
    Hmmm. Now for some more questions... Was the crank welded on? If it was - was it ever demagnetized? Did it have the backfires since newly built? You say it was "pro tuned" - was it running right then? Did all of this rough running just recently start?
    No the crank was not welded on, I asked then engine shop that balanced it, if they would, he forgot to weld it lol. No backfires ever and it has been running good for the past month then one day i'm leaving work and it cuts off in the parking lot..i fire it up and drive it, get gas, drive home. then i cant get it out of the garage the next day..trouble shooting everything and turns out it was VATS..i still dont understand what would cause VATS to shut it down all of a sudden. So i disabled VATs and now i have idle surge.... and cant drive it
    Reply With Quote Reply With Quote
  8. 04-04-2017 #8
    Brownvette
    Brownvette is offline
    Tuner in Training
    Join Date
    Jan 2017
    Location
    South Carolina
    Posts
    15
    Its almost as if the computer isnt telling it what the STFT or LTFT should be, like it isnt calculating...the last two logs i posted show towards the end of the log stft just flat lines, and ltft never moves at all. If tried a new MAF and same result, scan shows MAP to be reading correctly..O2 sensors do oscillate it seems..but they stay pegged out bc its running rich
    Reply With Quote Reply With Quote
  9. 04-04-2017 #9
    GHuggins
    GHuggins is offline
    Tuning Addict
    Join Date
    Jan 2015
    Location
    Franklin, NC / Gainesville, Ga
    Posts
    6,815
    Sounds like it's losing it's memory and or part of the calibration then - I wouldn't drive it if you don't have to... Not sure getting a used ECM is the best route either as 10SS pointed out - no way to completely write one without using OE stuff...
    2010 Vette Stock Bottom LS3 - LS2 APS Twin Turbo Kit, Trick Flow Heads and Custom Cam - 12psi - 714rwhp and 820rwtq / 100hp Nitrous Shot starting at 3000 rpms - 948rwhp and 1044rwtq still on 93
    2011 Vette Cam Only Internal Mod in stock LS3 -- YSI @ 18psi - 811rwhp on 93 / 926rwhp on E60 & 1008rwhp with a 50 shot of nitrous all through a 6L80

    ~Greg Huggins~
    Remote Tuning Available at gh[email protected]
    Mobile Tuning Available for North Georgia and WNC
    Reply With Quote Reply With Quote
  10. 04-04-2017 #10
    Brownvette
    Brownvette is offline
    Tuner in Training
    Join Date
    Jan 2017
    Location
    South Carolina
    Posts
    15
    Quote Originally Posted by GHuggins View Post
    Sounds like it's losing it's memory and or part of the calibration then - I wouldn't drive it if you don't have to... Not sure getting a used ECM is the best route either as 10SS pointed out - no way to completely write one without using OE stuff...
    Yeah I def dont drive it, I just wanted to see if maybe it needed to relearn something...thats exactly what i figured that its losing part of the memory or its somehow corrupt, the seller has a good rep on this forum apparently..spareecm, they write the factory OS to the ECM according to your VIN.
    Reply With Quote Reply With Quote
  11. 04-12-2017 #11
    Brownvette
    Brownvette is offline
    Tuner in Training
    Join Date
    Jan 2017
    Location
    South Carolina
    Posts
    15
    Turns out it was indeed a bad ECM!
    Reply With Quote Reply With Quote
  12. 04-12-2017 #12
    schpenxel
    schpenxel is offline
    Moderator
    Join Date
    Mar 2014
    Location
    Raleigh, NC
    Posts
    6,347
    Glad you figured it out
    Reply With Quote Reply With Quote
  13. 04-12-2017 #13
    Brownvette
    Brownvette is offline
    Tuner in Training
    Join Date
    Jan 2017
    Location
    South Carolina
    Posts
    15
    Quote Originally Posted by schpenxel View Post
    Glad you figured it out
    thank you sir! I appreciate your help and everyone else who helped out too!
    Reply With Quote Reply With Quote
  14. 04-08-2019 #14
    EddieD
    EddieD is offline
    Potential Tuner
    Join Date
    May 2018
    Posts
    8
    Did you replace the ECM or have a Dealer flash it back to factory configuration?
    Reply With Quote Reply With Quote
  15. 05-07-2019 #15
    Pistolpetep250
    Pistolpetep250 is offline
    Tuner in Training
    Join Date
    Dec 2018
    Location
    Spokane, WA.
    Posts
    13
    Quote Originally Posted by Brownvette View Post
    Turns out it was indeed a bad ECM!
    What did you do to get the new ECM installed? Did you go to the dealer and have them install/flash it or did you just buy one and install/flash it yourself?
    Reply With Quote Reply With Quote
« Previous Thread | Next Thread »