3.5 years ago (!) when I first bought the VEMS 3.3, I had some project for my Volvo 850.
Since then I had a Maserati biturbo and so I was more involved during my spare time with mechanics than with electronics or software. Hopefully the car is 200km from where I live !
Trigger
This biturbo has an odd fire engine
- with bizarre triggers
- do you have more details on the trigger ?
- VR/HALL ?
- pulse positions
so that the distributorless biturbos produced at the end were more easily equiped by Maserati with 2 ECUS, each one dealing 2with an 1/2 engine which is then 3 cylinders even fire.
Recently I aimed to use Vems to measure C0% at idle in order to fine tune the A/F potentiometer set on the Weber injection ECU.
My first issue is that I did not get the good O2 percentage for the free air test !
After you measure connection (including that you have +12V on heater+), you need to calibrate:
- GenBoard/Manual/Config/WidebandCalibration starting value (from RCal measurement)
- MembersPage/PhatBob/UserGuide - calibration steps
Wiring
Document wiring here !!!
email conversation suggests serious miswiring (like fused grounds)
You should start from 0, documenting the whole setup
- every wire you connected.
- every measurement
mcd/mct dump
Verify wbo2 config, and publish mcd / mct dumps.
email conversation suggests possible misconfiguration (although not confirmed)
Wbo2 is working
(01/09/08) What I did.
Following your advices, I have restarted from the begining using initial the Wbo2 configuration, megatune miniterminal and the config and upload .bat files.
Initial config.
wbo2_warmup_ramp=9C
wbo2_warmup_target=FF
wbo2_abs_limit=E4
wbo2_limit_maxt=A0
wbo2_fallback=60
wbo2_retry_t=06
wbo2_edgetime_corr=00
wbo2_edgetime_min=50
wbo2_ri_target=00
wbo2_nernstdc_target=9C
wbo2_pump_pw_zero=63
wbo2_calibration=AE
wbo2_heater_pid_kp=45
wbo2_heater_pid_ki=11
wbo2_heater_pid_kd=1A
wbo2_heater_pid_ilimit=81
wbo2_pump_pid_kp=15
wbo2_pump_pid_ki=20
wbo2_pump_pid_kd=00
wbo2_pump_pid_ilimit=FF
wbo2_ri_confidence_scale=80.
1) pump_zero test : I get 44.1mV -> good
2) 2x100 ohm test : Pin5-Ground : 3.98V -> good
Pin1-Pin5 : 0.241V -> bad
3) nersnt_dc_target : 9C -> A0
edgetime_corr : 00 -> BA
Pin1-Pin5 : 0.241V -> bad
4) ri_target : 00 -> 96
Pin1-Pin5 : 0.233V -> bad
5) nersnt_dc_target : A0 -> C0
Waiting 32mn or so for an 02 value to display as it is said!!
The trick is that this value may be not displaid, one as to mesure a stable dc value at Pin1-Pin5, so I got
Pin1-Pin5 : 0.530V -> bad
and
nersnt_dc_target : C0 -> B0
Pin1-Pin5 : 0.385V -> bad
but Hourrah the set point of the pump control loop can be trimmed!
6) Then it is easy,
pid_illimit = FF (get rid of hard bound),
pid_ki 20 -> FF
as it is asked, there should be a trick in the algorithm since the set point has to be reached whatever the ki value
Pin1-Pin5 : [0.500,0.530]V(instable)
7) Next I lower pid_ki to get a stable value, and I adjust nersnt_dc_target.
I finally got
Pin1-Pin5 : [0.449,0.451](good)
using:
wbo2_warmup_ramp=9C
wbo2_warmup_target=FF
wbo2_abs_limit=E4
wbo2_limit_maxt=A0
wbo2_fallback=60
wbo2_retry_t=06
wbo2_edgetime_corr=BA
wbo2_edgetime_min=50
wbo2_ri_target=96
wbo2_nernstdc_target=9C
wbo2_pump_pw_zero=63
wbo2_calibration=AE
wbo2_heater_pid_kp=45
wbo2_heater_pid_ki=11
wbo2_heater_pid_kd=1A
wbo2_heater_pid_ilimit=81
wbo2_pump_pid_kp=30
wbo2_pump_pid_ki=40
wbo2_pump_pid_kd=00
wbo2_pump_pid_ilimit=FF
wbo2_ri_confidence_scale=80
This is not a fine tuning, since one should adjust the control parameters with respect to the frequency band which is needed (AFR value for each cylinder?, noise?)and I changed the pid_kid value for no reason.
9) finally I calibrate for the sensor using : calibration = BA.
I put the sensor 10 centimeters inside the tail pipe to measure AFR. I obtain, for one pipe an AFR value of about 16 (no O2 value), and an O2 value of about 9 on the other (no AFR value).
Too much air.
The exhaust pipe is new, so the exhauts manifold is cracked (which happens on the Biturbo) or the sensor still catch some air from the end pipe?
Q. How deep inside the pipe should be set the wbo2 sensor to give a true value ?
SJ7
Q.If I input Vems with the signal from the VR cam sensor, can I output the
calibrated pulses from SJ7 which seems to be connected with the
Ref Pulse Output of the LM1815 ?
A. yes, the output of the LM1815 is a good place to "tap" the signal. Just make sure it does not get 12V or other damaging signal.
Problem with the miniterminal serial link
. The serial link from the Megatune miniterminal to Vems used to work without problem on my older notebook (Windows NT).
I tried to make it work using my new notebook Toshiba wich is equiped with a serial port. After some attempts and plays (!?) I got in response to man the following garbage:
man $Pw ´´´´´´´$(Px ±²±±±±±(,Pw™ª«©©©©©,0Pv•¡¢¡¡¡¡¡04Pu™›ššššš48PoŽ8<Pgzƒ„„„„„<?P_oxxxxxxx?<P_oxxxxxxx:<P_oxxxxxxx:<P_oxxxxxxx:<P_oxxxxxxx
(2@ABCD (2<KZijklm
. I immediately tested back the Vems communications with the older notebook: I get now the same garbage in response to man, however the megatune display shows the gauges correctly and active.
The audit log seems allright :
+++
Comm port = 1
Comm rate = 9600
Timer interval = 50 (I have tested some other values)
+++
. Next I tried to communicate through the keyboard and the LCD. I get the Hello message on the LCD but I was only able to make work the left and right arrows of the KBD. The KBD is an AZERTY and is a COMPACT model, but even after AZERTY/QWERTY translation, mcd or other commands do not work. However I remember that the COMPACT KBD are special.
Q. For what reasons do I now get that garbage in response to man?
Thank you for your help
A: Type Man not man!
26/10/08 - Thats'it ! (it was an easy one ;) )
Same week end, I made a special tubing for the wb02 to insert into the tail type. I measure an AFR > 15. My exhaust line is new but the exhaust manifold is possibly cracked (very common on the biturbo). Same day, I did not have more success with offEngineTesting of the input trigger...
Output trigger / coil type input trigger configuration
I connected the stim-output signal to the InputTrigger with a 1K resistor as said on the Output Trigger page.
I entered msp0a and I obtained a nice rectangular signal period 20ms, then I configured
primary_trigger 0x01
tooth_wheel 0x04
tooth_wheel_twidth1 0x0A (I did not try 0x2D or 45 deg)
trigger_tooth 0x01 (why not)
secondary_trigger 0x02 ( coil type no cam)
Result : no RPM value on the megatune gauge !
(I also tried the 36-1/no cam configuration and some others ...)
Back home to night, I browse the Wiki for any coil type/no cam configuration example or for some step by step guide which tells how to run this test, but without success.
Q. What is the configuration which works in this case?
I am afraid that, if left by my own, this basic test is going to take me another 3 months ;)
Trigger 4+0
With the help of the uk forum I realized that the trigger configuration "4+0" (why not to have the distributor still used ?) I was looking or more easily "4+1" should be handled only by the recent firmware version.
So I tried to upload version 1.1.43Alpha2
- Check everything running as usual
- Save of config and tables
- mci -> "Hardware serial number: V3.2-n00???"(I badly noted the end number) This surpises me since the order says V.3.3..
- mdV -> 1.0.23
- 1st run of upload-firmare-12x12.bat -> "LoAddr= 0 HiAddr=e73b" then "No hello from AVR"
- 2nd run -> ... "AVR said hello" "Flash erased" "-...-" then garbage/binary sent to the screen (1sec for each 80 bytes line), why not echo of the writing I thought, after waiting 4 hours I computed that this should be enough and I stopped the process.
- Power on/off and 3rd run -> "LoAddr= HiAddr=e73b" then "No hello from AVR"
- check megatune and miniterminal : dead
- run upload-firmare-boot-12x12.bat -> "didn't get reply from AVR, out of sync"
Now I am stuck...
Answer : If it successfully uploaded the new firmware, com speed is now 19200 and it outputs AIM binarydata. Check UK forum thread http://vems.hu/www.vems.co.uk/forum/index.php?topic=653.0 Also this trigger type isn't successfully tested so you are on your own with this.
- That 4+0 idea of configuration was for bench test only.
- Indeed the changelog of version 1.1.43alpha2 says that 19200 is now default. I tested the (nice) uploader script but I forced 9600 com1. I also tried to launch the Megatune but have the message "Megasquirt controller code version - received ???? from controller"
What about the 4 hours of binaries sent to the screen. It probably shows that the upload had failed. Is the boot firmware still allright set for 19200? What to do if not? Do I have to upload the boot firmware?
What about the mci telling my harware is version 3.2? Is Vems 3.2 compatible with the updated firmware?
Anyway some tests to do the another weekend ...