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Thread: Stand alone 1.4 engine swap

  1. #1
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    Stand alone 1.4 engine swap

    I have a 2012 Cruze 1.4 swapped into an autocross car. I'm having trouble with the VSS signal source. I can produce a working VSS with the Calibrate option in a Dakota Digital box, but if anyone has a method of tuning one of these engines WITHOUT a VSS source, I'd love to know about it.
    There is an option under transmission General, that selects VSS sensor NONE. Has anyone tried that?

    The 1.4 is mated to a Volvo 4 speed transmission. One option is install a digital speedometer drive, but I'm reluctant to do that.
    If I'm going to create a VSS source I'd rather do it off a front wheel.

    I'm new to tuning, but have done many engine swaps.
    No one has ever accused me of taking the easy way out.

    PS, the 1.4 now (as of yesterday) has an upgraded Garrett turbo on it. As long as I supply the fake VSS it runs like gang busters.

    Del Long

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    I did find an option under transmission to select VSS = None.
    I turn VSS off and the MPH reads 158 MPH, but the RPMs won't go over 4500.

    PS With the OTC (over the counter) tune from Trifecta it turns 7500 with 22 PSI boost and 22 CFM air. That's with the generated constant VSS of 49 MPH.

    OH, I should go back and see if the speedometer corection can bring the MPH down to 50 or so. I'll try that tommorrow.

    Del

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    Things I learned today. DO NOT attempt to load a tune that has VSS = none, AND an external signal supplied VSS attached to the ECM at the same time.
    You WILL brick the ECM. It become incommunicado. No communication at all. No code reader, no editor, no scanner.
    I didn't realize what happened the first time, and then I did it again.
    So I'm on my third 2012 Cruze ECM.
    It's a good thing they only cost $45.00 from Ebay.

    New question. Does anyone know how to wake up a bricked ECM?

    I assume the answer is NO.

    My new procedure is, 1. to turn off the external VSS. 2 load the tune. 3, turn on the external VSS. 4. Start engine run tests.
    Todays test with external VSS and BNR/HPTuners tune nets 30.9 lbs/min @ 27 psi, 7000 RPM.

    Del

  4. #4
    Advanced Tuner caesar's Avatar
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    Did you by chance try to flash it with the ignition in ON position instead of RUN? That is the only sure method to brick an E78 that I'm aware.

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    It's in a race car. On off switch only. Fuel pump and fans separate switches.
    Del

  6. #6
    Quote Originally Posted by sprinto7 View Post
    I did find an option under transmission to select VSS = None.
    I turn VSS off and the MPH reads 158 MPH, but the RPMs won't go over 4500.
    That is the VSS Sensor Location.

    "No Sensor" means ECM is trying to get VSS Value via CAN.
    In Standalone-Application there is no Source for the vehicle speed, so the ECM says 255 km/h (158 MPH).

    But from what I found out the ECM then thinks the vehicle ist standing and therefore limits engine power, boost and revs.

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    That sounds logical.
    I'm getting satisfactory results by piping in 50 MPH signal from my Dakota Digital box in calibration mode. However, it ain't perfect. It screws with the idle speed, and throttle pedal feel.
    I see some tables in the transmission section that has options that seem to indicate idle speed at various gears and MPHs. I haven't tried messing with those yet, but may try them, AFTER I get another spare ECM from EBay.
    It's pumping 32 lbs/min @ 30 psi, but only far very short burst test in my 300 foot driveway.
    Revise that. I got the WG back under control and it now at reasonable boost numbers.
    Thanks
    Last edited by sprinto7; 10-22-2015 at 09:16 AM.

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    Update, I have now successfully tested 2 wire magnetic sensors "reading" magnets in the 4 front brake rotor mounting bolts, and 3 wire proximity sensors "watching" the 8 one inch holes drilled in the brake rotors. Both signals are too weak to activate the VSS signal, but running either signal through a Dakota Digital SGI-5E Universal Signal Interface Unit makes the speedometer function correctly.
    Now we need to test under real conditions to see if the heat Kills the sensors.

  9. #9
    Quote Originally Posted by BadCop View Post
    That is the VSS Sensor Location.

    "No Sensor" means ECM is trying to get VSS Value via CAN.
    In Standalone-Application there is no Source for the vehicle speed, so the ECM says 255 km/h (158 MPH).

    But from what I found out the ECM then thinks the vehicle ist standing and therefore limits engine power, boost and revs.
    If I select "No sensor", how would I get a VSS signal reading through the CAN BUS?

  10. #10
    Modern vehicles have no VSS sensor.

    They get vehicle speed from ABS rings -> ABS-Module -> ECM

  11. #11
    So what kind of signal does the ABS module send to the ECM and through what pin? How can this be faked?

  12. #12
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    Hey Del its Chris. I just saw this post and thought I'd read up as we are going to be firing up the jeep soon and as you know hoping to run hptuners

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    Quote Originally Posted by ATLsilverSS View Post
    Hey Del its Chris. I just saw this post and thought I'd read up as we are going to be firing up the jeep soon and as you know hoping to run hptuners
    Well, I'm glad you checked in. I just trying to figure out who to get a hold of with some Jeep/LNF questions.
    1. is there a little "blackbox" on the J-1 that sends a VSS signal to the ECM? I can NOT remember if I used one on the car.
    2. If there is, make sure you don't have that BB powered up when you load a tune.

    Del Long

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    Quote Originally Posted by BadCop View Post
    Modern vehicles have no VSS sensor.

    They get vehicle speed from ABS rings -> ABS-Module -> ECM
    OK, I'm not going to dispute that, but I don't think that is totally true. On the E78, and the E39 Manual transmissions there's a top mounted VSS sensor that feeds directly into the ECM/PCM/VCM, and on the E78 at least those VCM inputs work for providing a Speedometer source. I can supply a wiring diagram if desired.

  15. #15
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    Quote Originally Posted by sprinto7 View Post
    OK, I'm not going to dispute that, but I don't think that is totally true. On the E78, and the E39 Manual transmissions there's a top mounted VSS sensor that feeds directly into the ECM/PCM/VCM, and on the E78 at least those VCM inputs work for providing a Speedometer source. I can supply a wiring diagram if desired.

    If you've got one handy that would be great. Just shoot me an email. The clutch ships Tomorrow so once we have that and I get it installed and button everything up she'll be ready to fire up.

  16. #16
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    Quote Originally Posted by ATLsilverSS View Post
    If you've got one handy that would be great. Just shoot me an email. The clutch ships Tomorrow so once we have that and I get it installed and button everything up she'll be ready to fire up.
    2012CruzeVSS diagram1 copy.jpg

    That was NOT easy. Had to bring into PS as .pdf, then save it a .jpg. I wonder what your going to get?

    2016-03-27

    I have tested this VSS input multiple ways.
    1. Magnets mounted into the four mointing . bolts on front brake rotor, read by two wire sensor.
    2. Proximity sensor pointed at the eight holes in the race only brake rotors.
    3. Magnets mounted into four holes drilled into, non slip, front Ujoint, red bu two wore sensor.
    Each of these inputs is fed into a Dakota Digital SGI-5E to convert the signal to digital sign wave. Speedometer correction is provided by the same box.
    Del Long
    Last edited by sprinto7; 03-27-2016 at 02:43 PM.

  17. #17
    Tuner in Training DanSchafer93's Avatar
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    Quote Originally Posted by sprinto7 View Post
    2012CruzeVSS diagram1 copy.jpg

    That was NOT easy. Had to bring into PS as .pdf, then save it a .jpg. I wonder what your going to get?

    2016-03-27

    I have tested this VSS input multiple ways.
    1. Magnets mounted into the four mointing . bolts on front brake rotor, read by two wire sensor.
    2. Proximity sensor pointed at the eight holes in the race only brake rotors.
    3. Magnets mounted into four holes drilled into, non slip, front Ujoint, red bu two wore sensor.
    Each of these inputs is fed into a Dakota Digital SGI-5E to convert the signal to digital sign wave. Speedometer correction is provided by the same box.
    Del Long
    I realize this is an ancient post, but Del if you have a tune handy, what were your speedometer setting in HP tuners? I have a different engine running the E78 ECM and am trying to use a 2 wire sensor to the Dakota Digital SGI-100BT for VSS because I too am super limited on power and am running a manual trans.

    Thanks,
    Dan

  18. #18
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    Sorry it took so long to answer. I haven't been here for quite some time. I now just pipe a signal from the Intake cam Pos sensor and hook it to VSS. It logged a MPH to HP Tuners but way off. I just kept changing it till it was close to the correct MPH. Of course its only correct in 2nd gear.

    I also have a 5Volt VSS gear in the tail shaft of the T5 transmission. I hook that directly to VSS also but it has come lose from the trans and failed at the very wrong time.
    Last edited by sprinto7; 01-16-2021 at 12:02 PM.