Wide Band O2 + data logger for 84-89 Carrera

[scarceller]

I've been working on the install of a very nice WideBandO2 + RPM data logger on my 84 Carrera and thought I'd share some of my project details.

At first I set out to find a decent AirFuelRatio (AFR) wideband sensor based gauge but I quickly realized I needed more. I decided that AFR readings alone are not enough and wanted to also log RPMs and AFR at the sametime. I also wanted to be able to dump the logs to a laptop. So these where the basic requirements.

The first product I looked at was the LM-1 but it alone can't log and I would need extra boxes/hardware to capture RPM and then the Logger as well. Kind of pricey at well over $500.00 for all this capability. With that said, if all you need is a wideband AFR gauge in your dash the LM-1 is very nice. But if you wish more then it gets kind of bulky and expensive.

What I found was a WBo2 logger made by TechEdge (see:http://www.wbo2.com) the model number I choice was the '2J1'. Sold by TechEdge out of Australia for about $180.00 AUD with shipping. This comes to about $150.00USD! Then I bought the Wide Band Sensor from Autozone (part #17014) for $50.00 and a few extra parts like connectors and epoxy and for around $200.00 total you have a great solution.

The 2J1 not only is a WBo2 logger but also logs RPM as well as 2 other 0-5volt input signals. So for my 84 Carrera I decided to log WBo2, RPM, AirFlowMeter Signal and the WOT switch signal.

The best news is I just finished wiring the 2J1 into my car and did NOT modify or touch a single harness in the car to install it! I wired it directly into the DME, sort of a piggy-back on the DME. (pictures in next post) This meant I did all the wiring on my workbench, I just took the DME box out from under the seat and went to town on the bench.

You could wire to the DME harness if you wish but for me I choice to wire directly into the DME. If you wish to do this I suggest you have good soldering skills, if you don't then just wire to the harness. Also a little scary is the idea of drilling a hole in the DME's front plastic connector to get the wires in.

Finally I used the software TEWBLog.exe to do the actual logging and displaying of the data onto my laptop. This means I must have the laptop in the car for seeing the results. You can also get software for a palm if you wish. Get the TEWBLog.exe from http://www.devtechnics.com/tewblog.htm.

Also available is a gauge that plugs in at the same point the laptop does. So you can use the gauge or the laptop but not both. I think the gauge is about another $140AUD. I did not get the gauge since I only plan to use the 2J1 for tuning and then remove (unplug) it from the car and put back the stock O2 sensor.

I'm a software guy so I would most likely go with a palm device for a perminant install and not a simple gauge. The palm can view all signals and not just the AFR + I think it could log data as well. You can get a used palm for $100 to $200 bucks so why just get a simple gauge?

See next post for pictures.

[scarceller]

Pictures here:

Here's the TechEdge WBo2 model 2J1 $150.00:


Here's the WBo2 sensor Part #17014 from AutoZone $50.00


Here are some pics of the wiring to the DME:








Switch that allows the 2J1 to simulate a Narrow Band sensor, flip switch on for Closed Loop mode and off for Open Loop mode. This allows the DME to still function as if the stock O2 sensor was installed.


Schematic for wiring the 2J1 to the DME

[scarceller]

Sofware details will come soon, will include images of the software in action as well as Microsoft Excel graphs of the data aquired.

[pmajka]

subscribed!

[Javers]

great thread, subscribed. Are you planning to write your own chip to finely tune your A/F ratios once you've collected all the data?

Jon

[ianc]

Looks very cool Sal; waiting to hear more!

Any news on the alternative fuel injector front yet?

ianc

[scarceller]

Originally Posted by ianc

Looks very cool Sal; waiting to hear more!

Any news on the alternative fuel injector front yet?

ianc

Want to keep this thread on topic, but this data logger is what I need to finish to evaluate the new injectors. I plan to log WOT AFR numbers across the RPM range for the stock injectors first then install the replacements and compare. You get the idea. So I need to finish this AFR logger to finish the injector work.

[scarceller]

Originally Posted by Javers

great thread, subscribed. Are you planning to write your own chip to finely tune your A/F ratios once you've collected all the data?

Jon

Very intresting you ask this question. I plan to look at the results of the AFR values against the RPMs at WOT and mid range. Then I have a theory or plan on howto tune our carrera cars with just an adjustable fuel pressure requlator for WOT. I'm fairly certain that the amount of fuel sent into the intake at WOT is fixed and if you just alter fuel pressure you could tune these cars for WOT.
Then for mid range tuning I'll just adjust the AFM via the spring tension and the other base adjustment. I figure idle will be easy. Of course this will only work assuming I don't see dips or peaks in the AFR for certain RPMs, if this is the case I'll need another chip. Also, this car is already chipped by PO through Steve Wong, just looking to see where I'm at.

The other reason I'm logging the AirFlowMeter signal is because I believe the AFM bottoms out at or about 4000RPMs, meaning that after this point the AFM is fully opened. Waiting to see the logs to confirm this. I have read this before and would like to know for sure. If it does bottom out it means the DME could only base the fuel intake on the RPMs and the WOT switch after this point. We shall see.

[jbrinkley]

very nice work, I wish I was that good at electrical stuff.
and just so there's no confusion, the lm1 with rpm converter does log afr, rpm and any four more signals you wish to use, and does work simultaneously with laptop as it records. And does have two outputs for whatever, (remote gauge). and it's less than five hundred.
there are less expensive options now out there than there were before. Some better, some not.

I'm not nit picking, just putting the real info out there. I wish someone would come over to my house and wire up my fuel press and boost signal to my WB.

[scarceller]

Originally Posted by jbrinkley

very nice work, I wish I was that good at electrical stuff.
and just so there's no confusion, the lm1 with rpm converter does log afr, rpm and any four more signals you wish to use, and does work simultaneously with laptop as it records. And does have two outputs for whatever, (remote gauge). and it's less than five hundred.
there are less expensive options now out there than there were before. Some better, some not.

I'm not nit picking, just putting the real info out there. I wish someone would come over to my house and wire up my fuel press and boost signal to my WB.

I'm not against good information and as I said the LM-1 is a great device, was just to pricey for me since I only plan to use it for tuning. So how much would it cost to get an LM-1 with RPM and 2 more inputs? Include everything, like the software and the WBo2 sensor.

The TechEdge solution I'm trying comes in at under $250.00. No I hope it functions well or I just blew $250!

Please do provide details for the LM-1 if you know the full picture and cost. Do you have the LM-1?

[jbrinkley]

http://www.innovatemotorsports.com/xcart/product.php?productid=16152&cat=261&page=1&xid=2db610708e693dd79958151aa8391601

this is what I have, plus a remote digital gauge in the dash that was $15
I've slammed on innovate before about prices, if you search there is a ton of info about logs on here, pics, screenshots, the works.
Let us know how this less expensive solution works.

I forgot to add, innovate has a great forum with many people posting and all the answers one would need
here http://www.innovatemotorsports.com/forums/index.php

[scarceller]

Today I played some more with my 2J1 wideband device.

I logged a 140 second run (1400 data points) from idle 850RPM up to 4200RPM and back down to 850RPM. The run was done with un-loaded engine, meaning done while parked and in Nuetral in the garage. I then took the data and ploted the RPM vs AirFuelRatio in Microsoft Excel here is the chart:



The run was done with no O2 sensor signal being feed into the DME.

Then I started to play with the Narrow Band signal that's simulated by the 2J1 unit and learned that you can customize the maps so that you can alter the Narrow Band simulated output. This is very neat feature because ussually our cars, when run with the stock narrow band O2 sensor tend to want to set the AFR to about 14.5 but in my car it has a sweet spot of about 13.5, so I have tuned the car to run at 13.5 across the RPM range and if I plug in the stock O2 sensor the DME adjusts the AFR to 14.5. So I'm now toying with customizing the Narrow Band simulated output from the 2J1 to trick the DME into thinking that 13.5AFR is equal to 14.5. This would be great because what it will do is feedback actual AFR from the 2J1 to the DME via the simulated signal and then the DME will (at idle and mid-throttle) always hold true to my selected AFR wich happens to be 13.5.

Think of it this way: the DME will run in Closed Loop mode just like it does with stock O2 sensor but I'll be able to set/tune the closed loop mode to the desired AFR, I get to pick the AFR!

Will keep you posted.

[Javers]

Very nice work sal, I never realised that you can tune the "emulated" o2 output. This could result in some nice fine-tuning abilities.

Jon

[fly4val]

When I first started reading this, it wasnt clear to me what could be
accomplished...however, further reading provided a bunch of
info and enlightenment to this old 'mechanical' guy....thank you....

[scarceller]

More results:

Since my new TechEdge WideBand O2 sensor has a Narrow Band simulated output (NBsim) I have feed this back into the DME's Narrow Band input pin and I have found some real neat features of doing this. First, the NBsim is fully configurable: by default it has a built in simulation curve (built via a 65 point data map that can be altered) the default map simulates a standard NB O2 sensor so that it is set to cross at about 14.7AFR (lambda). If I leave it set to default and feed the signal to the DME then the AFR goes to 14.7 across the RPM range so long as not in WOT mode. It stays rock solid at 14.7 across the RPM range. Keep in mind the DME while in WOT mode ignores the O2 signal, so this only works up to the point that the WOT switch makes contact.

So this configurable NBsim output got me thinking and I created new maps that set the cross over for the following AFRs:

* 13.5
* 13.7
* 14.0
* 14.3
* 14.5
* 14.7 (default one)

The maps look like this graphed:

!

So I just started wit the default 14.7 map as the base and started shifting the curve downward to achieve all the other maps.

Now the real cool part is that if I just feed the NBsim into the DME's NB input and select the map I wish to use it sets the AFR rock solid for the give map!

One other thing is that these WB O2s responde extremely quickly (10ms or better) and this produces very simular response times on the NBsim output, I've compared the NB input signals from the stock NB O2 and they are no where as responsive as the NBsim created by the WideBand module.

I'm very impressed with the results from a simple <$250.00 addition to the car

[scarceller]

Install Update:

I had to route the WideBand O2 signal wire harness from the drivers side SSI into the cabin under the drivers seat. I simply routed it through the same hole that the main Wire harness goes through to the engine. The hole is located right below the rear jump seat (drivers side) I just pulled the rubber gromlet out of the hole while the harness is still in it. I then carefully cut the gromlet to get it off the harness then trimmed it a little so that I could acomidate the extra WideBand O2 sensor harnes and routed the new WBo2 harnes through the hole and put the gromlet back around the orginal engine harness and the new WBo2 harness.

The harness that came with the WBo2 unit was just long enough and required NO monification. Although it was tough to get the large black connector through the existing hole, but it fit.

Will take some pictures soon.

[ianc]

This may be a diversion (or a hijack), but it seems a pretty good place to ask: what is the difference between and narrow band and wide band O2 sensor?

ianc

[scarceller]

Ian,

Please read this
http://www.team-integra.net/sections/articles/showArticle.asp?ArticleID=390
it has a full description of why Wideband is a must.

Originally Posted by ianc

This may be a diversion (or a hijack), but it seems a pretty good place to ask: what is the difference between and narrow band and wide band O2 sensor?

ianc

[ianc]

Very informative. Thanks Sal!

ianc

[jbrinkley]

cool, stuff
did you know that the nb signal is ignored at all but idle and part throttle cruise?

Fine tuning is in the chip and altering idle mix will have nothing to do with afr's at wide open throttle.
It just seems easier to force (unplug NB o2) the afm to run at an idle mix of your choosing than to fake out (send an emulated signal) the DME.
A perfect motronic FI system doesn't need the o2 sensor, it compensates for worn out components in the system, withing it's capabilities.
But I totally understand about playing around and messing with stuff, you should see my car.
If you haven't read the mortonic/jetronic/K manual I highly recommend it.
But if you're totally afflicted, reading that will just make you want to buy more parts.