Can't get nistune running

  • #1

    Can't get nistune running

    I've got an '86 na2t. Runs fine with my stock '86t ecu, and ran fine on my '86NA ecu before getting it nistuned. The nistune'd ecu is part number 18P03.

    Now if I try to start the car with the nistuned '86na ecu, it may start sometimes but it won't idle and seems to run too rich to stay running, if I race the engine I can barely keep it running. Runs fine again after putting the stock '86t ecu back in and clear out the fouled plugs.

    The car has no EGR, Idle control/IACV etc, only one line for boost sensor and one line for fpr, and there doesn't seem to be any leaks. CHTS and subharness are new. Cleaned the MAF. Not running any o2 sensor.

    I've tried applying the stock '86 tune from the rom pack and that didn't seem to change anything. I think I'm then supposed to resize the injectors via the k constant but that didn't seem to affect the behavior, and may be moot since the car at least ran on the stock 86na ecu / tune…? I've gone over the manual too many times and I'm pretty stuck here.

    I tried recording the nistune log when trying to start it and race the engine, then it dies and I try a few more times. Hope this helps. https://drive.google.com/file/d/1ieI…ew?usp=sharing

    If you have a tune worth trying for me to share, I'm running stock maf and injectors at the moment. Just trying to make sure this is all working right before I get it to a shop for real tuning

    (waiting on account approval over at the nistune forums)

    Thanks guys and gals
    Last edited by drnict61; 06-23-2020, 01:41 PM.
  • #2
    You've tried running the 86 *turbo* tune, right?
  • #3
    Originally posted by FrozenZ View Post
    You've tried running the 86 *turbo* tune, right?
    Lets see if I'm doing this right…

    Launch nistune, select my vehicle (either 1986 z31 or 88-89 z31 produces the same results)
    Select my tune (either 86 18p03 tune which is the NA or 86 19p03 Turbo tune produces the same results)
    Click Consult to connect to ecu (I get what's pictured here: https://imgur.com/a/8E5u7Bb, same results whether I select yes or no)
    Upload and burn tune to board
    Test start, fails
    Clicking Change MAF shows that it does not have one preselected, selecting the z31 maf I get a popup saying "MAF HP Figures unavaiable. Adjust load multiplier manually for MAF."
    If I click Resize Injectors, the correct CC (260) is already filled in
    Apply tune and try test start, still fails

    Eh?
    Last edited by drnict61; 06-24-2020, 06:28 PM.
  • #4
    Does it matter that the vendor didn't ask me what ECU I had when they shipped nistune? Again it's originally an '86NA 18P03

    EDIT: Confirmed with vendor the nistune board should be compatible with my ECU, so I'm overlooking something I suppose
    Last edited by drnict61; 06-29-2020, 10:35 PM.
  • #5
    Matt helped me figure it out.

    I was being a big dummy, instead of using the 26p0f ROM for the nistune board, I kept thinking I was supposed to use the ROM that matches my original ECU part. Big derp.

    Car starts and runs fine now. Time for the shop woot woot!