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Historical: Old hunting after/during some home conversion of input-triggers
Not really sure what is going on here, but none of my IGN outputs are working...
The box is installed in my (M52 w/ HALL/HALL setup) E36 BMW, I had to convert the box from VR to Hall on the pri trigger, everything else seems to work just fine (P259, INJ, etc) but I cannot get any reaction from any of the IGN outputs no matter what I configure them as even in "test mode"
Any ideas?
Generic hint: first setup and test triggers independently from any outputs. Just the triggers, watching InputTrigger/TriggerLog
I've tried reloading and changing firmwares and nothing has helped.
12+ and GND, and EC36 pinouts have has been verified and tested ok... using an LED to test the outputs.
here is one of the cfg's: http://vems.hu/vemstune/sharingcenter/reports.php?cmd=view&key=5wb985
so just to re-cap.. this is what I did to the board to switch from VR to HALL
is there something that I could have done here in the process like bridge trig1 that could have damaged something?? or by changing/removing a resistor?
I followed the V3.3 instructions from this page: http://www.vems.hu/wiki/index.php?page=GenBoard%2FManual%2FInputTriggerHardWare
soldering JP2 & JP7 didn't work for me.. the pri trigger didn't work with that soldered, but started to work with it unsoldered
changed R30 to 2k4 (strong pullup).
removed R56 completely, soldered blob @ SJ2, removed blob @ SJ6
Measured the blob @ SJ2 and have 3.8V to GND with hall sensor unplugged and the trigger's (both pri/sec working wonderfully)
- SOLVED: I later found that home-conversion of trigger most likely did not succeed because there was apparently a short to GND
- in the line coming from the voltage regulator (+5V or +5.5V ?) to the ignition chip (i259 ? Or some other ? Which line exactly ? Some lbus data or address or chip select line ?) which was causing my issues. I was unable to find where the short was and the ECU was returned to VEMS USA
JUNE 2017:
Running issues - Injector characteristics are wonky when IAC is being controlled. This issue isn't apparent in other BMW's which I have done
Background info:
injectors: measured resistance = .... Ohm ? All measure within 0.2 ohm of each other - going from memory 13.6-8
- type : ... Injector Dynamics ID1000 (EV14 base)
- size : ... 1000 cc/min
- Can you check and detail the flyback path ? Specifically what should I look for? I'm not too familiar/never had to do this before.
- also measure all IAC and inj outputs in use with DVM: low voltage flyback is recommended for IAC outputs; If DVM diode mode measures <1.9V between output and EC36/23 as a base, that is good for IAC. Else (perhaps not requested any injout with low voltage flyback), easy to use BY399 diode (or STPS340U SMB or ER2J or ES2J or SS24 SMB diode, or even 1n4007 for max 1A load), cathode on EC36/23 (some hides it in the boot at the connector).
- Stock E36 factory BMW wiring harness with Motronic (55?) plug cut off and various sensor/outputs removed from harness (NB O2, SAI, etc)
- IAC originally wired to INJ 7+8 (Dual solenoid)
- ID1000 Injectors
I have been struggling with poor injector control since installing this box many years ago, also been struggling with odd/inconsistent IAC control but am unable to understand if it is the IAC control of due to Inj. control.
Symptoms:
During light loads and under 80 kpa/constant throttle applications the car feels like it slows down and has a step in power.
Finally the other day I happened to be playing with IAC PID's so I was on the standard IAC page of VT. I happened to notice that the issue start and ends when the IAC starts to count down to 0, and once the IAC position reaches 0, the car bucks and seems like it gains about 20 hp and lurches forward.
Now that I've noticed it, I've been able to consistently recreate the issue and it is timed perfectly with IAC movement/shutdown.
Nice find ! Check that you have low voltage flyback for IAC outputs, and not for injoutputs used for injectors.
- it is also possible, that the 1.5ke30 transient diode inside the ECU, or the big 4.7uF 63V foil capacitor at the flyback rail got damaged somehow (or broke down, or sg).
- Is there a way to test if it's damaged?
Tests:
So far I have attempted disconnecting the IAC, this immediately resolved the driveability issues at light throttle (especially in parking lot driving).
I have since moved the IAC from INJ 7+8 to IGN outputs, unfortunately IAC control now is very, very poor and has limited range (seems like IGN output is not strong enough or maybe lack of fly back is the cause?
- yes, definitely lack of flyback, obviously when used on ignout, use diode outside, very easy, do that first
- Motor likes to stall often and run at very low RPM when cold (even though DC is higher).
Example. on INJ output, DC table was between 70-30% but on IGN outputs DC table is at the min 80-100% and this doesn't give enough adjustability.
Logs are as follows:
- This log is driving with the IAC connected to INJ output as it has been for 4+ years, and at some point towards the end of the log I disconnected the IAC @ the connector and drove about 2-3 min more to final destination for test w/ no map/tune changes at all: http://www.vems.hu/files/MembersPage/Sascha/SCHNELL-E36/v3.3_u006414-2017.06.19-16.52.18.vemslog
- This log is a short drive with IAC still disconnected, but with some VE changes: http://www.vems.hu/files/MembersPage/Sascha/SCHNELL-E36/v3.3_u006414-2017.06.19-19.34.19.vemslog
- This log is a long drive with IAC put on IGN output, and tuning/VE changes being done throughout: http://www.vems.hu/files/MembersPage/Sascha/SCHNELL-E36/v3.3_u006414-2017.06.19-21.39.05.vemslog
As an extra note, I happened to be at a friends house that has M52 swapped E30 w/ VEMS that I installed/tuned, this car along with others do not exhibit this issue at all! So here is a small log example (was out tuning the AC/IAC input: http://www.vems.hu/files/MembersPage/Sascha/SCHNELL-E36/v3.3_u006804-2017.06.19-20.54.55-DAVE_E30.vemslog
Suggestions on settings
- There are BMW IAC valves which have spring-loaded default position for a limp-home mode at ~30-40% opening. Looking at your first log above it seems to me that a +10kPa jump in MAP is apparent when the IAC value reaches 0. I think this is the point where the ECU disables energizing the valve, and the valve is jumping from the energized closed (0%) position to the spring-loaded default position. You can check this behavior by manually forcing IAC positions and plugging of the valve in-between. If there's no change to idle RPM you've got the IAC valve default position equals to its spring setting. After that, set this position as the minimum in IAC settings and force close, that way you can avoid such jumps in MAP. Hope this solves your problem! (GergelyLezsak)