MembersPage/PeteKrgr/Oldstuff (2007-11-16 13:52:23)

Update 17-07-07

After these wiring changes and checking config I managed to get RPM to MegaTune. However there's no spark or fuel. I have current flowing to WS coil and injectors, but nothing further, like Genboard doesn't send any signals. Config should be correct, at least it's set according to installation instructions. Wiring is checked too.

Update 01-08-07

Reason for no spark and fuel was this brilliant "Installation instructions" found from Wiki...it says there that for WS coil one should use 5V logig level output. However when reading from Bosch WS-coil's information page you can see that it requires 12V output. While I do not have a Bosch coil I hadn't looked that page earlier. But now, when close to despair, I did some searching I found this and changed pins. Now it works.



WBO2 calibration problem

Tuning of the car is at the moment quite difficult, because I cant't calibrate my WBO2. I followed instructions found from MembersPage/PhatBob/UserGuide with no success. It says:

"Once the heater is up to temperature the O2% reading will display a value rather than question marks. We now need to adjust the calibration value so that the O2% reading is correct. The earths atmosphere is 20.9% Oxygen, we'll settle for a figure close to that.

RPM:0000 W00I00 P099

009F 77, 10EC D3 P

00 F1 00 00 0DDD

AFR=? O2%=20.9

To change the wideband calibration value type Manmttg8bcA8mcs and then type mll a few times to get an idea of the average value that its displaying. To increase the calibration amount increase the hex number after Manmttg8bc from A8 to A9, AA...AF while checking for changes by typing mll."

So command Manmttg8bcA8mcs gives O2% of 12.8, command Manmttg8bcAFmcs gives 13.0% and max hex of Manmttg8bcFFmcs gives just 16.0% . Quite far from 20.9%, isn't it??

Sensor is a BOSCH LSU-4 from VEMS web shop and the Genboard is calibrated. What's the reason and how to solve the problem?? AFAIK I'm not alone with this...one fellow Finn had similar issue and it was solved when he changed the sensor to one that came with Innovate LC-1.


Pete, you can use LCD and keyboard to heat up the sensor and get it to show O2%, and just open MT and adjust WB calibration constant from there (Settings -> Wideband settings -> Calibration constant), results are visible "live" as soon as you change the constant. You can verify that it's spot on by shutting down the heater (mde00), ECU and then heating it up again. MembersPage/PeepPaadam

Thanks Peep, I just tried this, but the calibration constant was already at 254 ( and the max is 255 ) so this wasn't helping.

MembersPage/PhatBob Are you 100% sure that the sensor is clean? I had person with a similar issue, his sensor had become contaminated, after 10minutes with the heater on, there was smoke, a bad smell and then the O2 started to rise...

I just tried one new, ie unused sensor with similar results. And I torched my sensor with propane, no change.

For info, I did some measurements mentioned in User Guide ( for calibrating WBO2 controller cicuit ) and got these values.

WBO2_pin5 - GND 4.08V

WBO2_pin1 - WBO2_pin5 0.45V

WBO2_pin5 - WBO2_pin6 -60mV

Other specs in the text way above...

Is there anything to do/measure??

I have also checked my wiring, all connections at right places and wire impedance ( looping two wires at a time ) is 0.5 ohm.


You could flash the ECU to 1.0.73 firmware and see how WB acts on that. It's a 5minute task. MembersPage/PeepPaadam

Problem solved. It works better ( = warms up ) if the +12V is connected. I had fused it together with fuel pump, and I take fuel pump fuse off when I do not run the engine because of noise and battery life... I checked all other wiring except this ssupply several times.

Anyway, it's now calibrated. if there's something good in this, I've learned quite much about MegaTune, terminal program and using the LCD.


Update 20-10-07

I finally found the reason for the problem I've had with my car all the autumn. It has been burning fuel in exhaust from time to time and idle has been also very rough, but not consistently. I thought I had trouble finding correct settings, but one ignition plug was not functioning correctly. This has caused much delay in tuning and solving minor issues, like

-while ICV is functioning, it clicks at approx rate of 4-6 clicks / second. What should I adjust to remove clicking?

-while ICV is functioning, idle rpm is high despite the throttle is fully closed. Is adjusting the iac_ref_pos the correct way to solve this?

One bigger issue: Pulse Width in MegaTune remains in 0.2ms all the time. Is this an indication of malfunctioning hardware or software??