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View Full Version : Wide band O2 w/ digital display in car



kuhnga
10-15-2003, 08:12 AM
SOME WHAT AFFORDABLE AT AROUND $430
5 WIRE O2 SENSOR IS $139 ITSELF

http://www.techedge.com.au/

I will be getting one soon, anyone else interested?




TECH NOTE FROM A USER

In my case a few years ago while on an chassis dyno some simple tweaks with the ECU yielded 20 more rear wheel Hp. On the other end of the spectrum bad tuning can lead to poor derivability, low power, and in the worst case a blown engine. With this in mind, and my ultimate goals when it comes to my car, I decided perhaps it would be wise to invest in a device that would tell me just how well, or poorly, my car is tuned. Such a device is called a wideband oxygen content (or Lambda) sensing unit. Similar to the factory oxygen sensor, found in every car, it measures the oxygen content in the exhaust gas stream. Without getting into the exact chemistry of combustion , since combustion is a result of igniting fuel and air (oxygen) the resultant oxygen content in the exhaust will tell you how much "extra" oxygen is left over after the process is complete. This indication will enable you to determine whether there is enough, too much (rich), or too little (lean), fuel being added for combustion. So why not use the factory oxygen sensor? The factory O2 sensor is a narrow band sensor. In other words it can only determine oxygen content in the exhaust gas close to what a stoichiometric combustion would produce. So those Christmas tree A/F ratio gauges seen often - I had one too - are ok for indicating something major is wrong but should never be used for serious tuning. Stoichiometric...Ooooo, big word! Stoichiometric in layman's terms is basically combustion that uses exactly the right amount of oxygen to combust the fuel added. For gasoline this value or ratio is 14.6 but it can have values between 14.4 and 14.7. So the factory oxygen sensor is perfect for conditions where stoichiometric combustion is desired, i.e., at idle. Stoichiometirc combustion is good for emissions. Also the factory oxygen sensor only operates under certain conditions where it provides feedback to the ECU to add or subtract fuel. It does not provide feedback when the engine is under load or boost. To continue, under loaded conditions stoichiometric combustion is not a good thing for many reasons. Fuel, for example, is good at cooling the combustion mixture (same principle as water injection) thereby reducing the likelihood of pre ignition. Similarly, because ignition timing is never exact some added buffer to determining fuel mixture is also a wise decision. There are also a myriad of other reasons why a richer mixture is necessary. Given that desired fuel mixtures under loaded conditions fall outside the accuracy "band" of the factory oxygen sensor a sensor with a wider accuracy "band" is needed. A wideband sensor has the ability to accurately measure exhaust gas oxygen content for fuel mixtures that are both very lean and very rich. (here for details of how a wideband O2 sensor works) So what makes the wideband and narrow band different? Well part of it is to do with the fact that a wideband sensor is heated. This provides a baseline from which the sensor can take measurements. As the sensor is measuring essentially a chemical reaction temperature correction is imperative. As such a simple narrow band sensor has one wire, a wideband sensor will have at least five. Now the sensor itself does not tell you what the air to fuel (A/F) ratio is, it merely provides an output voltage. It is therefore up to a bit of computer wizardry to convert this voltage into a useable A/F value and to do it quickly enough so that's it's somewhat meaningful. Easy...right? Not to do inexpensively. Until now! See... there's a couple of computer geeks down in Australia who also happen to be car guys who decided to put together their own wideband Lambda sensor. The control circuitry for guys like this I'm sure was fairly straightforward, the key was in finding a suitable, affordable sensor. Well thanks to Honda there is one. Apparently Honda in 1995 decided to use a wideband "5-wire" sensor in a Civic. Without going into details this sensor can be found at any reputable parts supplier or Honda dealer (if in stock). Yippeee!

wHAT YOU GET

Originally sold as a Do-It-Yourself kit, as in they supply you with a bag of parts (resistors, wires, capacitors etc.) and you solder the circuit boards together, TechEdge started selling prebuilt units recently (also referred to as the DIY OZ Wideband Kit). Yeah! I did not fancy the idea of assembling my own unit. The only part needed was for the purchaser to acquire the O2 sensor itself. Having read much about the DIY-WB on the Datalogit (datalogging software for the PFC) list I decided to buy a prebuilt kit. And the beauty of the setup is the price, I paid a total of $269.00 (including shipping from Australia) for the kit and $139.00 for the UEGO sensor. Comparable kits/units from, for example, FJO are on the order of twice this cost. The original DIY-WB version (vers 1.0 which I purchased) is currently in use by thousands. Per the TechEdge website it provides: Reliable analogue measure of AFR using the NTK L1H1 sensor (the Honda sensor mentioned above), measurement of AFR from below 10 (unleaded) to above 30 (VERY wideband!), useable with 13.2 Volts (the car should be running), has a single red LED indicating sensor is heated and Ip is enabled, and provides a voltage output (Vout) of 1.4 (rich) to 2.5 (stoic) to 3.1 Volts (lean) and with no user adjustment and automatic calibration with sensor's recalibration circuitry.

So what is it I bought? The kit (all the parts I purchased - sold individually) comes with TE-5301 Wideband LED display with RS232 aux connector (hopefully some day to be used for datalogging with the Datalogit), a 2.6 meter sensor cable (comes with the Sumitomo connector to fit the Honda O2 sensor connection), and the WB unit itself. These all arrived as advertised, all the way from Australia in about a week. The sensor (Echlin Part Number: ECHOS791) I purchased from my local NAPA for $139.00, special order - took about 3 days. And when I received all this great stuff...it sat on my workbench for 4 months! UGH! Actually I was doing some research and thinking on how to do the installation. For example the sensor is extremely sensitive to it's location in the exhaust system. Something to do with the delta in temperature between the sensor heater and the temperature of the exhaust gas. But per the TechEdge folks; the sensor should always be placed on the engine side of a catalytic converter (this one should be easy), the gas temperature to the sensor should never exceed 850 degrees C (about 1560 degrees Fahrenheit), the sensor should never be run without power to the WB unit (a hot sensor burns off carbon residues), always have the long axis of the sensor perpendicular to the gas flow (stops sensor clogging), position the sensor vertically or at most between 10 o'clock to the 2 o'clock position (this avoids cracking the internal ceramic structure should moisture condense internally) - this one would be the toughie, and a specially welded additional bung is the best mounting strategy

JJanney
10-15-2003, 09:16 AM
Widebands are extremely useful. If you gave me a month, maybe I'd get one too. :) Check out the Lambda Boy (sp?) wideband. My roommate has one and the company is very good about repairs on bad/defective units.

fastsc92
10-15-2003, 11:12 AM
my buddy found a nicer set-up than that for cheaper. I'll get you the link. Here it is. http://www.innovatemotorsports.com/
Very nice product, give it a try. I think it looks cleaner and has more functions and its only 350

kuhnga
10-15-2003, 12:20 PM
fastsc92--I think that does look better, is your buddy happy with it , how long has it been around?

Gary

fastsc92
10-15-2003, 01:25 PM
he hasn't purchased it yet, but plans to. He just has been doing some research and found this to be a great product. Also, it must be good because it won a sema award. I'd give it a try.

DLF
10-15-2003, 07:09 PM
I use FJO's in both my cars. More expensive, but more options also. Datalogging, PC display, and now they're coming out with a 2 1/16" display.

http://www.fjoracing.com/

http://www.fjoracing.com/newimages/FJOWIDEB.JPG

dode
10-17-2003, 09:47 AM
I have a question about this sensor. First, was it only used in 95 Civics? Is it the exact sensor that comes with the kit? IE, does it have the same connector with the calibration resistor in it? Is the calibration the same as what is listed on that website? I could really use a wideband for a race car and this would be perfect. I am definitely interested in this project. It could really help me out.

John

SonySC
11-05-2004, 11:59 PM
my buddy found a nicer set-up than that for cheaper. I'll get you the link. Here it is. http://www.innovatemotorsports.com/
Very nice product, give it a try. I think it looks cleaner and has more functions and its only 350

I'm having trouble getting a reading from my left Oxy Sensor since installing Kooks mid length headers.I've changed to a new Bosch but get very little signal variation on my Air-Fuel gauge. I'm thinking that maybe the placement in my downtube is too far away or maybe just a bad spot. The right one works just fine. Can I buy a better wide band sensor an have it couple to my stock eec?
George Clarke aka the SonySC@hotmail.com 925-984-3785 cell

BT Motorsports
11-06-2004, 12:50 PM
I'm having trouble getting a reading from my left Oxy Sensor since installing Kooks mid length headers.I've changed to a new Bosch but get very little signal variation on my Air-Fuel gauge. I'm thinking that maybe the placement in my downtube is too far away or maybe just a bad spot. The right one works just fine. Can I buy a better wide band sensor an have it couple to my stock eec?
George Clarke aka the SonySC@hotmail.com 925-984-3785 cell
Yes, the Innovate system allows you to send a signal out to the stock EEC to mimic a narraow band while the LM1 is using the wideband data for its own purposes. Drop me a line if you need more info, I am an Innovate dealer.

Paul

SonySC
11-06-2004, 07:32 PM
Yes, the Innovate system allows you to send a signal out to the stock EEC to mimic a narraow band while the LM1 is using the wideband data for its own purposes. Drop me a line if you need more info, I am an Innovate dealer.

Paul
I'm having trouble with my left Oxy Sensor.I just replaced my stock ported (broken) manifolds with a set of Kooks midlength headers and my left sensor won't work. I replaced it with a new Bosch unit and I am getting some deflection on my air/fuel guage but not enough to keep my EEC happy, throwing codes. I had the muffler shop make up new downtubes with extra bungs and plugs for dyno tuning as well as replace my cats.
I'm thinking that I might try moving the left sensor to the other bung and see if position has anything to do with it. When I removed the old one(not so old), It was all black and sooty as I know i'm running a little rich. I want to get everythig squared away before takeing her down for a good dyno tune and setup. It is really running great but would welcome a little better gas mileage at $40 tank fillups of 91 octane.
I've heard that someone makes a wide band sensor that can replace the stock sensor and is compatable with our EECs and still have the extra wire for dyno tuning. Do you have anything like that?
I'm running 42# Ford Motorsport injectrors on a fairly well modded engine and 3.73s so will welcome any power and economy increases to be had.
George Clarke aka the SonySC@hotmail.com 925-984-3785 cell

sail7seas
12-04-2004, 11:55 AM
This might be another alternative?

From http://www.bahntech.com
BahnTech's $159 Auto Dyno includes everything you need to collect Horsepower and Torque dyno data on your vehicle. If you need a low cost high quality dyno or Dynamometer for your automobile you choice is simple: Auto Dyno is the worlds most inexpensive Dynamometer (Dyno) and is still packed with features you would expect from units costing thousands of dollars. Features including Graphing of Horsepower and Torque, Speed. RPM, G Force, Distance and up to 4 [0-15v] analog inputs. The Auto Dyno has 4 inputs to log data during your Horsepower run including Throttle Position, Mass Air Flow, O2 Sensors, etc.

Read more about Auto Dyno here http://www.bahntech.com/products/Auto_Dyno/dynos.asp