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S54 E30 redlines at ~5800

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    S54 E30 redlines at ~5800

    I'll try to be terse bc I don't want to read a huge block of text either...
    For reference, here's my build thread: http://www.r3vlimited.com/board/showthread.php?t=381366

    S54 swap running earlier this year. ECU swap/tune done by a local shop in Dallas. Finally get everything broken in and try to rev it to the sky but I hit redline at around 5000. I take it back and they reflash it as they forgot to enable/disable (whichever is correct) dyno mode. *1*
    At that point, it would rev over 5000, but I can't remember for sure if I was able to take it to 8200 or not - I don't drive this car very often or very far, and I live in a crowded as hell part of DFW.
    I drive for a while, but keep getting a VSS code popping up. I go back to the shop and have them reflash it - VSS code goes away but the guy I spoke with isn't quite sure how the guy doing the tuning did it. *2*
    A month or 2 later I go and pay for some dyno runs, and the car absolutely will not go above ~5800; it seems just like its banging off a rev limiter. Tried with sport mode on, sport mode off, cleared adaptations, unplugged battery for a day then plugged back, etc, etc, etc.

    Took it back to the shop today and they pulled the flash, looked over everything, and the dyno mode is set properly and the rev limit is set to 8200. They can't find anything wrong with the software.

    *1*: any chance this is dyno mode somehow re-enabled? Some box not checked....or unchecked?
    *2*: with OBD2 readers, the VSS still doesn't display a number. My guess is it was flashed out instead of coded to actually read the VSS off the E30 sensor as discussed in another thread in this section. Could this have anything to do with it?

    IMO, there is no mechanical reason to have a consistent redline at 5800. The redline is controlled solely by the ECU.
    The car runs strong, pulls hard...absolutely no codes at all. Definitely not in any kind of limp mode.
    If the transmission was hosed, it wouldn't be a consistent redline at 5800 in every gear.
    If the wiring was hosed, I think it would either be intermittently redlining at 5800 (ie a short), or have a variable rev limit.

    Can anyone think of ANY reason besides purely the software that this would happen? If it is the software, or someone can look at/root through the software, I can/will send you my ECU, bc I can't get INPA to work on any of my 3 computers. I don't like not being able to fully enjoy the car so any ideas are much appreciated!

    Or - does anyone in DFW (or Houston, since I will be there over xmas) have either an E46 M3, or an S54 E30 that I can swap my ECU into a see if it redlines at 5800 in a different car? That was it will at least point to either the ECU or my car.

    #2
    The S54 ECU gets the speed signal from the ABS not the diff like the E30/36s. Without looking up the exact gear calculators, I would say the 155mph speed limiter is kicking in...software issue.

    Never heard of a dyno mode setting, but maybe such a thing exists

    Is it limited to 5800 just reving in neutral? I have an S54 E30, but I am in Tyler. MSS54HP ECU with Epic alpha N tune.

    Comment


      #3
      That was one of my thoughts as well. Instead of changing the VSS to read the 9 pulse signal and adjusting by appropriate K factor of 7784 (http://www.r3vlimited.com/board/show...&highlight=vss), I feel like they may have just turned the VSS signal off all together and this is the result. Apparently the 155 mph limiter gets its signal from the VSS itself and not the speedo, which would make sense why this is happening if it is indeed the cause.

      Dyno mode is something that should be enabled, or else the car won't go past 6500.

      No, it isn't just limited to neutral. In neutral as well as every gear I have tried it in (haven't tried 5th, 6th, or reverse lol) it won't go past 5800-6000.

      Comment


        #4
        What software version do you have? Can you share your partial DME dump?

        Comment


          #5
          Definitely sounds like it's VSS related. Without VSS signal going to a tune that doesn't have the VSS coded out (not just the CEL disabled) you will be rev limited. Gear is determined by RPM + speed.

          Diesekte made the next point I was going to make.
          Try to keep VSS if you can, it's much less headache to just hook it up than to get a properly working tune without it.

          Comment


            #6
            All they did is erase the error code. They didn't do proper coding. You are hitting 'safe mode' rev limiter. Also in safe mode, vanos is not being adjusted, so you are losing power. Shop does not know how to tune it properly all they did is take your money. Next time buy from me and you won't have a problem

            Comment


              #7
              What software version do you have? Can you share your partial DME dump?
              I haven't been able to get my vagcom cable working on any of my laptops recently. Coincidentally one of my laptops just went south and is now rocking a fresh Win7 install. Any known working places to get the FT232RL chipset cables, or do I have to just roll the dice on some random China plastic?

              If I can't ever get a cable to work though, I'll have to send the DME to someone with the ability to fix the VSS issue and/or look through the file

              If its not the VSS issue, I imagine it being somewhere in the software. I just can't imagine any sort of mechanical reason for this to happen. Not saying it's impossible but way less likely than the software I think.

              I use ultragauge...if anyone isn't familiar its an OBDII tool that wirelessly gives you real time data for the vehicle sensors to your android etc. It gives pretty damn accurate info for rev, MAF load, fuel trim, coolant temps, etc, etc...but the value for vehicle speed has always been (and still is) 0...

              Comment


                #8
                I bought this

                And modified the cable with these settings using
                FT Prog

                I would utilize 328iJunkie for his flashing services if you want a surefire solution. Of course others can help as well. IMO the most fun is to fix it yourself to not rely on others :-)
                Last edited by R3Z3N; 12-20-2016, 11:51 PM.

                Comment


                  #9
                  There is a Dyno mode limiter and a standing limiter (what people modify for launch control). Your vss isn't wired or coded propery and it's more complicated than just suppressing vss code to make DME happy with no signal at all.

                  I can help remotely.

                  Check Us out on Facebook
                  Needing a harness adapter or wiring help? Check it out: also have 24v motor mounts, E30 M3 covers and E36 ECU mounts!
                  Full Product Line Tuning
                  OBD2 Tuning Available! OBD2 E36, S54 Swap, S62 Swap, etc: tuning@MarkertMotorWorks.com Dyno Thread

                  Comment


                    #10
                    FWIW,
                    Standing limiter stock is 6k
                    "Dyno" mode is 6300

                    Check Us out on Facebook
                    Needing a harness adapter or wiring help? Check it out: also have 24v motor mounts, E30 M3 covers and E36 ECU mounts!
                    Full Product Line Tuning
                    OBD2 Tuning Available! OBD2 E36, S54 Swap, S62 Swap, etc: tuning@MarkertMotorWorks.com Dyno Thread

                    Comment


                      #11
                      Originally posted by DesertBMW View Post
                      All they did is erase the error code. They didn't do proper coding. You are hitting 'safe mode' rev limiter. Also in safe mode, vanos is not being adjusted, so you are losing power. Shop does not know how to tune it properly all they did is take your money. Next time buy from me and you won't have a problem
                      Dont buy anything from this clown.

                      The 5800 limiter is safe mode but its not neccesarily VSS related. MSS54 can be configured to read the 9 tooth signal easily but there are lots of reasons it could be in limp mode.

                      Who flashed it? Have you talked to them?
                      Build thread

                      Bimmerlabs

                      Comment


                        #12
                        I ended up sending the ecu to Dave. Hopefully he can go through it and see what the issue is. It does not throw codes in obd2 but there are still a few issues in INPA, that are mostly emissions related AFAIK.
                        It was flashed by a BMW shop in Dallas that honestly has never done me wrong otherwise, and has been pretty legit in trying to work through this with me, so I'm trying not to name name until this gets resolved. For all I know I know it could be my car, so I don't want people putting them on blast if it ends up being my fault somehow.

                        Comment


                          #13
                          Issues now resolved thanks to Dave/MMW. Got the ECU back and it is like a different car in the few short minutes I had time to play with it today.

                          In short, the VSS was not modified correctly, and the standing limiter was at 6000 as suspected....among some various other issues that have been fixed by the MMW tune. They did me right when the car still had an M52 and saved the day a second time.

                          Now to get this thing dyno'd again...That is originally how I found out about this issue. I wasted money on a dyno session only to make 244 @5600 rpm

                          Comment


                            #14
                            nice work Dave!

                            now what kind of power does it make at 8000RPM!!!!


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                              #15
                              Originally posted by 328ijunkie View Post
                              There is a Dyno mode limiter and a standing limiter (what people modify for launch control). Your vss isn't wired or coded propery and it's more complicated than just suppressing vss code to make DME happy with no signal at all.

                              I can help remotely.
                              I have same issue how to fixed rpm safe mode

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