My daily driver, Audi S6 avant -95, 2.3L inline 5, 20 valve turbocharged engine (AAN).
Installed VEMS as direct replacement of original ECU (see PlugAndPlayMotronic) using factory wiring. Extra wires are needed only for WBO2. There are some modifications with the trigger wires as well (swap secondary VR signal wires in 3pin JPT connector on firewall)
The engine is now running well, some tuning is still ahead.
Some open issues to solve
- Tachometer is not always showing proper rpm value, sometimes it falls down to near zero for a very short periods of time. Needs still verification of original tachometer signal with scope.
Note about the time-saving effect of wiki-written documentation
It's notable that this install was carried out before other competing installs (despite that it was done in the cold, while competing installs had a warm garage host), because documentation discipline was appr 60%.
Competing installs have 10 and 40% documentation discipline so they lost, and might struggle for a few more days or weeks.
Even for this install, 3..5 days could have been saved with 90..100% documentation discipline, the firing order alone could have saved 1..2 days.
Megatune settings for 1.0.34 firmware package (22-Feb-2006):
mcd.txt and mct.txt (07-Mar-06):
Airtemp sensor data:
Some values to make verification easier: Note that pullup is 470 Ohm not 2700 Ohm
- -40,395 temp_internalformat=0, adc_read=117 (256/ (470+395) * 395)
- -20,425
- 0,457
- 20,490
- 30,503
- 40,520
- 60,555
- 80,585
- 100,620 temp_internalformat=254, adc_read=146 (256/ (470+620) * 620)
Note that the tables are quite steep. The MAT goes from min to max from position 0x75 .. 0x92.
For the prepared tables, look for "PTC" on EasyTherm
Flying wire adaptor for basic functionality from genboard (v3.3) towards motronic connector (pins Mxx)
- 5x high-Z injectors (INJA..E to M36,M17,M34,M35,M16, INJA = cyl #1 and so on)
- 5x ignition coils (with power output stages) (IGN00..04 to M01, M02, M23, M20, M21, IGN00 = cyl#1 and so on)
- so h[2]=03 01 00 02 04 ... required to match 53124 fire order as requested on InputTrigger/AudiTrigger !!!
- BoostControl solenoid aka WGFV (INJG to M33)
- Idle air controller (INJH to M04)
- Fuelpump relay (P259/5 to M03)
- Trigger signals
- 2x VR (M47 home signal, M49 rpm, M48 GND), home signal has inteverted polarity!
- 1x Hall for camsync (M08), InputTrigger/AudiTrigger setup
- GND and Supply voltages
- 12V supply
- M18 has 12V, M27 switched, to additional relay
- to board itself (EC18/25), from additional relay
- supply for injectors, relays (M37), from additional relay
- 5V to hall, TPS etc (EC36/28 to M12)
- 3x GND5 wires (M21, M24, M32)
- GND wire (M10, connected to engine), connect back to M30, GND for sensors
- 12V supply
- TPS sensor signal (M53)
- CLT (M45), IAT (M44) sensors, for IAT
- Tachometer (I259/7 to M40), 5V signal, divider=01
- Knock sensor (EC18/03 to M11 #1, M29 #2 unconnected)
- WBO2 sensor
- 5x extra wires needed
- original MAF connector is not used with VEMS. There are only 3 signal wires + gnd + supply, so MAF wiring is not usable for WBo2. Anyway, MAF uses 6-pin JPT connector, VAG part 022906233A for housing + 022906102B boot
Will add wiring diagram later..
Hardware changes made to V3.3 board
- Trigger related
- R182 shorted (instead of 100k in primary trigger)
- added 1uF cap in parallel with C40 (longer peak hold time)
- 10k pullup to 5V for crankhome VR signal (~40k may be enough, without C40 mod either option didn't work)
- crankhome VR inverted in firewall JPT connector, not as in original motronic (inverted works with motronic too)
- C103 replaced by 1nF
- All ign channels changed to logic level
- MAT pullup (R10) changed to 1k+1k in parallel (500 ohm) in order to work better with stock MAT sensor
- AREF shorted to AVCC (AREF=256)
We have expericenced some very annoying problems around 6000rpm in two different cars / ECMs using auditrigger setup.
Symptoms are either cut spark or excess amount of fuel and loud bang once things continue to work properly - but so far logs seemed to be ok. This behaviour doesn't seem to be depending on engine load and it is possible to see it without any gear engaged or in heavy acceleration. However RPM where this is seen is constant 5600/6100 and 5900 in other car. If one keeps on pushing gas pedal, engine will eventually gain rpm and gets over this point.
Some notes:
- MT doesn't seem to give warnings about trigger errors, but this has not yet been verified from LCD display
- Suspected too long dwell first, but lowered it down to 3.3ms -> no changes
- Tried different loads / mixtures, max DC% has been around 45%
- does the problematic RPM change if you move trigger_tooth (eg. by 3..4 teeth) and adjust ign_tdcdelay ? (beware of auditrigger's direction of trigger_tooth, verify with a timinglamp and mda28)
- We still haven't found reason for this problem. Logs give no hint about it.
Here is some data finally: http://kapsi.fi/~mpeippo/fileet/temp/VEMS.zip
- Another problem: When MAP gets below ~46kPa it will cause loss of about 30% of sparks (misfire, or short output pulse, or no output pulse at all?)
- I would say no pulse at all, not sure though
- Engine load (gear or MAP) doesn't affect this.
- not related to RPM ? Eg. same happens from 1000 .. 3000 RPM ?
- Same thing dependless of rpm
- Logs show only changes on lambda, nothing on spark or fuel.
- most basic data: firmware rev ? config / tables ?
- no spark-cut configured ? ALS (MembersPage/GaborRacz/NewAlsLaunchAndOthers) disabled ?
- No ALS
- no spark-cut configured ? ALS (MembersPage/GaborRacz/NewAlsLaunchAndOthers) disabled ?
- this is very unlikely to be trigger related. Isn't it possible that mixture gets lean in some cylinders ? that sounds like the most likely reason (but hard to tell without the basic data)
- We have two cars with both these problems (audi trigger), so it shouldn't depend on engine HW.
- are the engines the same, with same config and tables ?
- Engines and configs are ~same not tables
- are the engines the same, with same config and tables ?
Any ideas anybody?
Hey Miska,
what is the current status of the Auditrigger?Did you fund the pest pullup values yet??Im really interested to go with the stock trigger setup on my AAN/3B hybrid,instead of the sloppy 5 window hall!!!Please tell me your final resoults (special problems,what for watch out etc.),
thanks in advance, MembersPage/NanassyPeter
Trigger works just fine, all related HW modifications are as listed above:
Internal (in ECM case)
- C103 replaced by 1nF (instead of original 220nF on board). This is important
- R182 needs to be shorted (to charge peak capacitor from single pulse) (this improves noise immunity)
External:
- 10k pullups added to both VR-signals (but only crankhome signal needs this). Actually, it can be done inside the ECM case too.
- Secondary VR signal must be inverted. Easiest to do this on black 3-pin connector located to firewall, one pin is shielding, 2 for signals.