Wideband VOUT logging via TGV position sensor input

sideout909 · **Posted:** Thu Aug 05, 2010 2:07 am

Well here is what I got before I logged in and found all of the useful information dshultz just posted :mrgreen:

Code:

<parameter id="P40" name="Wideband O2 Sensor" desc="" ecubyteindex="13" ecubit="7">
                    <address>0x000034</address>
                    <conversions>
                        <conversion units="AFR" expr="1.2466666667(x/50)+10.18" format="0.00" />
         <conversion units="Lambda" expr="0.0866666667(x/50)+0.69" format="0.00" />
                    </conversions>
                </parameter>

I am going to be running E85 here in a week or so (once I get my Walbro installed) so I decided to have it convert for either Gas AFR or Lambda. I have the vout tapped into the left tgv input and my vout table looks like this now

Code:

AFR Lambda Volts
53   1.12   5
23   1.1   4.84
94   1.08   4.61
65   1.06   4.38
37   1.05   4.16
1   1.03   3.94
7   1   3.62
68   1   3.6
53   0.99   3.48
38   0.98   3.36
24   0.97   3.25
1   0.96   3.14
97   0.95   3.04
84   0.94   2.93
71   0.93   2.83
59   0.92   2.73
47   0.92   2.64
35   0.91   2.54
23   0.9   2.44
12   0.89   2.36
01   0.89   2.27
91   0.88   2.19
8   0.87   2.1
7   0.86   2.02
6   0.86   1.94
51   0.85   1.87
41   0.84   1.79
32   0.84   1.72
23   0.83   1.64
14   0.83   1.57
05   0.82   1.5
96   0.81   1.43
88   0.81   1.36
8   0.8   1.3
72   0.8   1.24
64   0.79   1.17
56   0.79   1.11
48   0.78   1.04
4   0.78   0.98
32   0.77   0.92
25   0.77   0.86
17   0.76   0.8
1   0.75   0.74
02   0.75   0.68
95   0.74   0.62
87   0.74   0.56
8   0.73   0.5
72   0.73   0.44
64   0.72   0.37
57   0.72   0.32
49   0.71   0.25
42   0.71   0.2
34   0.7   0.13
26   0.7   0.07
18   0.69   0

I got my Evo3 Big 16g a little while ago so this is going to come in handy for my OL Maf scaling!

sideout909 · **Posted:** Thu Aug 05, 2010 2:35 am

I noticed that dschultz input the equation into the xml without the parentheses so I just revised it a bit. Also I added it at the end of the parameters under a new id so the logger will still be able to log the Left TGV voltage (like I would need to do that :roll:

) About to hook up the laptop in the car and go do a pull :twisted:

Code:

      <parameter id="P204" name="Wideband O2 Sensor" desc="" ecubyteindex="13" ecubit="7">
                    <address>0x000034</address>
                    <conversions>
                        <conversion units="AFR" expr="x/50*1.2466666667+10.18" format="0.00" />
         <conversion units="Lambda" expr="x/50*0.0866666667+0.69" format="0.00" />
                    </conversions>
                </parameter>

sideout909 · **Posted:** Thu Aug 05, 2010 3:18 am

Here are 2 second gear pulls i just did. Looks like I have some work to do on the OL Maf scaling! Under boost it should be 11.1 and my sensor is in my up pipe :mrgreen:

edit: I think my equation is still a little off

mickeyd2005 · **Joined:** Wed Oct 25, 2006 12:32 am **Posts:** 3040

A sensor ini the uppipe won't work for boosted engines.

The pressure is too high and will skew the AFR.

sideout909 · **Posted:** Thu Aug 05, 2010 2:38 pm

Well dang looks like I'm gonna have to bust out the welder and throw it in my downpipe. I would put it in the rear o2 sensor bung but I can't get the bugger out. I've tried everything.. but a torch :twisted:

I'll swap it out today when I put my 16g on :mrgreen:

sideout909 · **Posted:** Sat Aug 07, 2010 6:12 am

So I settled on using JAW's factory output of 2x+10 just to simplify things. Works like a charm :mrgreen:

Just started tuning the 16g earlier tonight but it looks like I need to upgrade my fuel pump :roll:

All I know is I'm glad I had my wideband telling me I was going lean! Thanks for the help guys, I am very satisfied with the result.

Airboy · **Posted:** Sun Aug 15, 2010 12:39 am

I used the fuel level sensor input on the ECU to do the same thing back before LC-1 logging was integrated into the RR logger.

viewtopic.php?f=15&t=774

Good to know the TGV inputs can be used as well.

mike96 · **Joined:** Mon May 11, 2009 10:36 pm **Posts:** 8

so question, i have a wide band unit from WBO2.com and currently have it in my down pipe prior to the cat. i have my rear O2 CEL's disabled in my ROM and currently have one of the two programmable outputs (programed as a linear 0-1v output) wired into the rear O2 sensor input. this is how i log wide band in my eclipse using EVOscan, what would i have to change to get RR to display the rear O2 as AFR instead V?

Sasha_A80 · **Posted:** Sun Oct 24, 2010 1:04 pm

1. It is not required to limit the voltage by 1.0 V.
Almost all ecu's will measure O2 voltage up to 5.0 V.

2. correct such a string
<conversions>
<conversion units="AFR" expr="x/50*1.2505+9.6985" format="0.00" />
</conversions>

for your rear O2 sensor voltage readings in logger.xml

mike96 · **Joined:** Mon May 11, 2009 10:36 pm **Posts:** 8

thanks for that... i was having a little bit of trouble figuring out how you come up with the formula for RR. i read trough the thread a couple of times but for some reason couldn't figure it out... just curious how do you, in case i have to make any adjustments to get accurate numbers? also are you positive that the ecu can handle a full 5V input. i could swore that i had read somewhere that it was only capable of a little more that 1V (1.5ish)... or maybe i had read somewhere that the front could only handle about 1.5V...

dschultz · **Posted:** Sun Oct 24, 2010 11:28 pm

That formula is an interpretation of what the VDC to AFR curve looks like for a particular WBO2. Each manufacture is different. Basically it is the VDC value * some multiplier + a constant for a linear output. See viewtopic.php?f=7&t=6430&start=13 for an example. The repeat the process for your 0-1VDC signal.

ClimberD · **Joined:** Sat Dec 13, 2008 6:20 am **Posts:** 23

Wonderful thread! I had to quickly splice my AEM WBO2 into the Left TGV sensor since it wouldn't talk to Windows 7 via USB. Been working fine for weeks. Thank you for the code to save me from the darn y=mx+b conversion every new log file!!! Will plug that in later when I get some time.

mike96 · **Joined:** Mon May 11, 2009 10:36 pm **Posts:** 8

just a little FYI info for anyone that might want to try logging their WBO2 thorough their rear NbO2 input... i have my formula worked out pretty good however as per Sasha_A80's info unfortunately the rear O2 input on this ECU won’t read anything over 1.5V (it is actually something a little bit lower like 1.245XXXX but who is counting). i found this out by adding a "raw ecu value" line to RR and watching it while i played with the output settings on my WB unit. raw values fluctuated between 0 - 10 then my WB was set to 0 and topped out at 255 when my WB was at 1.25v. comparing it to my WB gauge it seems to be pretty close, i would say +/- .02AFR. here is what i ended up with, my WB is set to output a linear line from .01v to 1.24v 10AFR to 19AFR. i then added this line to the RR logger definition, that way i could switch it back and forth if need be.
<conversion units="AFR" expr="x/50*1.961+9" format="0.00" />

dschultz · **Posted:** Tue Nov 09, 2010 11:26 pm

Another option is connect the 0-5VDC linear output of the WB to pin 8 of the Tactrix OpenPort 2.0 connector. Then set standalone logger to log the internal ADC channel pin 8 and add your formula to convert VDC to AFR.

DisoDisp · **Joined:** Sat Jan 21, 2012 2:06 pm **Posts:** 45

Can someone explain the wiring to a complete layman?

I've got a AEM Analog Wideband, that has a White: +0-5V output and a Brown: -0-5V output. (According to the user manual http://www.aemelectronics.com/Images/Pr ... 0-5130.pdf)

Now, it seems like the Brown Negative output can be connected to sensor ground, and the White Positive output can be connected as usual.

How would I go about wiring these to the TGV sensor harness? (I assume, one pin is ground, one is 5V, and the third is a signal input?)
I.e. would I connect the White wire to a signal input, and the Brown to ground?

If, so can someone tell me which wire is which on the TGV sensor plug?

Thanks.

RomRaider

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