Exhaust sensor

[lelouchvi]

Firebass:
So is your first sensor locate just before the cat where the pipes meet ? So not in here as shown in the picture >>


and second one after CAT?

For mine setup, my first sensor is place just like the one in the picture.
The second one just left out from the exhaust as the replacement cat dont have a hole and the wires is not long enough for the second hole just before cat in the exhaust manifolds.
In Urban runs my fuel consumption is quite high, only about 50 miles max on 7.8 litre of fuel!
Hope you gusy understands!

[mr kawa]

There is someone here that told me there are "pteformance" o2 sensors that even helps out the obd2 that i have.
Does anyone know something about his?
Is there a point that the lambda needs to be changed due to age and accuracy?

Gr luuk

[BETEK]

Is there a point that the lambda needs to be changed due to age and accuracy?

Of course it is good change an old sensor to a new one.
Old oxygen sensors gathering dregs and tending to block.


Here is an article for "performance" (Wide Band) oxygen sensors:

Introduction
Up until relatively recently, all oxygen sensors were of a type known as narrow band sensors. The reason these sensors are called "narrow band" is because they are only able to tell us if the air/fuel ratio is above or below a single known amount or a single narrow range. It can tell us that the mix is either rich or lean, but it doesn't tell us how rich or how lean the mix is. More information about narrow band sensors can be found in the article, Oxygen Sensor Adjustment - General Information.

Wide band oxygen sensors are also called wide range oxygen sensors, air fuel ratio (AFR) sensors, or just A/F sensors. They are called "wide band" sensors due to the fact that unlike narrow band sensors, they are not only able to tell the computer if the air/fuel mix is rich or lean, but how rich or how lean it is. It is able to signal to the computer a wide range of air/fuel mix readings. This makes it much easier for the computer to make adjustments to the fuel trim to achieve it's targeted air fuel ratio.

These sensors are new, and weren't used in any vehicles prior to 1997. Starting in about 1999, nearly all Toyota models started using them. However, other than various Japanese and German makes, most automobile manufacturers have yet to adopt them. Because they are a superior sensor, we feel it's only a matter of time before they are universally adopted by all manufacturers.

FuelSaver-MPG now offers "Wide Band EFIEs" to deal with these new sensors. We have found that it's actually much easier to control the air/fuel ratio of a vehicle with wide band sensors and our new product than with our earlier EFIEs on older style vehicles. But we still need to know the basics of how these sensors operate, so we can work with them.

How the Sensor Signals the Computer:
Unlike narrow band sensors that communicate to the computer by means of a voltage on a single wire, the wide band sensor uses two wires and signals the computer by means of a current flow. An air/fuel ratio of 14.7 to 1 (by weight), is considered to be the optimum air/fuel ratio. When the ratio is above this value, the current flows in one direction, and when it is below this value it flows in the other. When the air/fuel ratio is exactly 14.7 to 1, the current doesn't flow at all. In order to signal increasing rich or lean conditions, the current flow increases in ratio to how rich or lean the air/fuel ratio is.

The two wires we are discussing are called the current pump wires. The reason they're called this is a bit more technical than I want to get in this article, but if you'd like to know more about this you can read this article.

The voltages on these current pump wires varies from manufacturer to manufacturer. One of the 2 current pump wires will have a voltage supplied to the sensor by the ECU. The other wire will be a return wire from the sensor to the ECU. Toyotas have 3.0 volts on their reference wire and the 3.3 volts on the current return wire. Note that the 3.3 volts will vary slightly as the current flows, but these changes are very tiny. Likewise, Nissans use 2.7 volts on their reference wire, and the current wire is approximately 3.0 volts. So far, in all of the 4-wire wide band sensors we've seen, the difference between the 2 current pump wires has been a nominal .300 (300 millivolts), that fluctuates slightly based on current flow.

5-Wire Wide Band Sensors
There is another type of wide band sensor that uses 5 wires, and sometimes 6 wires (rare). In this case there is a 5th wire that gives a voltage representation of the current flow on the current pump wires. When a 5th wire is used in this way, it will usually be called the "signal wire". The 6-wire versions also supply a ground reference for the signal wire. In both of these cases, there is circuitry to convert the current flow on the current pump wires into a voltage. But this type still uses the current pump pair of wires to control the voltage on the 5th wire.

The simplicity, as far as installation of our Wide Band EFIEs goes, is that we are looking for the two current pump wires, and we are attaching our device to the wire that has the higher voltage of that pair. If you find a sensor that uses voltages that are much higher or lower than those described above, you may have a misidentified wire or device. In this case, you should contact support@fuelsaver-mpg.com to get help identifying your vehicle's sensor wires.

The Heater Circuitry:
Wide range sensors require a tip temperature over twice as hot as narrow band sensors. The temperature also must be maintained within a predefined range. To achieve this, the 12 volts is pulsed to the sensors heater, and the "on" time of the pulse is varied as needed to keep the temperature in the proper range. We've also seen examples where the 12 volts is supplied constantly, but the ECU makes and breaks the ground connection in a similar manner. Either way allows the ECU to control the exact temperature at the tip.

Identifying the heater wires can be a bit tricky. When the 12 volts is being pulsed, and you read the voltage on your multi-meter, you will not see 12 volts. You will see a lower voltage, like 6 or 8 volts for instance. This is because the meter is trying to give you the average voltage over a period of time. If you have a frequency function on your meter, you would see the frequency of the pulses to verify that you had the heater wire. If the ground is being pulsed, then you will see 12 volts on the heater wire, and a ground reading that might not be stable.

Downstream Sensors
So far, every vehicle we've seen that uses wide band sensors, only uses them upstream of the catalytic converter. The downstream sensors have always been narrow band sensors. Further, with modern vehicles, we have found that you must treat both the upstream and the downstream sensors to be successful. This means that you must have an EFIE for each type of sensor, and if you have 2 upstream wide band and 2 downstream narrow band sensors, you'll need a dual wide band and a dual narrow band EFIE. At some point we will make this configuration in a single device, but at present you can find these EFIEs packaged together for a reduced price in our online store.

Summary:
Making modifications to wide band sensors has been a problem for people adding fuel saving devices to their cars. Particularly the 4-wire version of the wide band sensor (or AFR sensor) has just had no workable handling for modifying the air/fuel ratio. This has now changed with the development of our new Wide Band EFIEs. We are finding that these EFIEs can control wide band sensors of any type better than earlier EFIEs are able to control narrow band sensors. We are now able to achieve lower air/fuel ratios and hold to them more exactly than ever before.

http://www.fuelsaver-mpg.com/wide-band-oxygen-sensors

[mr kawa]

thats good information, so now i have been searching on several sites for a wideband oxygen meter for my 1.4 (obd2)
but the only thing i came across is a wideband sensor with a led display so you can check if your fuel/air mixture is the way it should be.. but this is not what upgrades preformance right? this is just a tool to find out whats happening in the inside..

[BETEK]

Wideband oxygen sensors don't increase power!
It is just a tool for proper ECU tuning.
In few words helps the ECU tuner to "read" the car emissions accurately and from that readings to configure properly ECU fuel cards for optimum power.

[BETEK]

FAQS from AEM website about widebnad oxygen sensor

Q: What is a wideband air/fuel UEGO Sensor?
A: UEGO is an acronym for Universal Exhaust Gas Oxygen sensor. It is the most accurate, fastest responding type of Air/Fuel Ratio (AFR) sensor available on the market today. UEGO sensors should not be confused with common “switch” type O2 sensors equipped in OEM vehicles that are designed to work within the parameters of a factory engine management calibration.

Q: Why do I need a wideband air/fuel ratio sensor controller?
A: If you are going to modify your engine in any way, knowing the Air/Fuel Ratio (AFR) is critical to achieve the best performance, and to prevent leaning out and potentially destroying the motor.

Q: I saw an O2 gauge online for $80, isn't this the same thing?
A: NO! The vast majority of O2 sensors are of a simple "switch" type. These sensors can only indicate whether your engine is running rich or lean, but not what your actual AFR reading is. For tuning purposes, these types are sensors are useless.

Q: I have an aftermarket fuel injection computer. Can I use an AEM Wideband Air/Fuel Controller Module or AEM Wideband Air/Fuel Gauge with it?
A: Yes. It has a 0-5v output so you can simply hook up the wideband air/fuel module to the O2 sensor input wire of your fuel injection computer.

Q: My AEM engine management system includes a wideband air/fuel controller. How can I monitor my AFR in real time?
A: You can use our Serial Datastream Gauge to monitor your AFR in real time. Our Serial Gauge works with AEM EMS systems only.

Q: Why does the controller include a sensor and a module? Is the module a heater controller?
A: UEGO-type air/fuel ratio sensors output a small current that must be conditioned and corrected based on a number of operating parameters. This is what the module does. Without the module, the sensor is useless. The majority of the sensor’s "brains" are in the module. Also included in the module is the heater controller, but it is only one part of the controller.

Q: Can I use a different wideband air/fuel sensor than the one supplied?
A: No. The supplied Bosch sensor is calibrated specifically for AEM Wideband Air/Fuel controllers.

Q: Where do I get a new wideband air/fuel sensor for my AEM Wideband Air/Fuel Controller from when mine goes bad?
A: You can purchase a new Bosch sensor for your AEM Wideband Air/Fuel Controller from one of our distributors, or by using the “Buy Now” feature on our website. The part number for a replacement UEGO sensor is 30-2001, and you can search for the product page with the “Buy Now” button using the “Search AEM’s Site” box located below the products menu on the vertical navigation bar. Or, click on the “Sensors and Connectors” page using our vertical menu. To purchase from one of our authorized dealers, please visit our Dealer Finder page using the link at the top right of the horizontal menu.

Q: I have a four-cylinder car. Which AEM Wideband Air/Fuel Controller should I use?
A: You can use one of our single-channel wideband air/fuel controller modules (Inline Wideband Air/Fuel Controller, Digital or Analog Wideband Air/Fuel Gauge, Wideband Failsafe Gauge or X-WiFi Wideband Air/Fuel & EGT Controller).

You can also monitor each cylinder’s individual air/fuel ratio using a 4-Channel Wideband Air/Fuel Controller module. The 4-Channel Wideband Air/Fuel Controller delivers the greatest accuracy and potential for power when tuning air/fuel ratio since it reads AFR in every cylinder chamber individually. If you have a forced induction engine, you can still mount the sensors pre-turbo by including AEM’s Backpressure Compensation Kit (PN 30-2064).

If you use and Inline Wideband Air/Fuel Controller and want to view your air/fuel ratio in real time, you will need to purchase an AEM air/fuel display gauge (digital or analog style). You can also monitor AFR from your laptop if you have a stand-alone engine management system with this capability.

Q: I have a V6, V8, V10 or V12 car. Which AEM wideband UEGO Controller should I use?
A: You can use two of our single-channel wideband air/fuel controller modules (Inline Wideband Air/Fuel Controller, Digital or Analog Wideband Air/Fuel Gauge, Wideband Failsafe Gauge or X-WiFi Wideband Air/Fuel & EGT Controller) if you want to monitor both cylinder banks.

You can also monitor each cylinder’s individual air/fuel ratio using multiple 4-Channel Wideband Air/Fuel Controller modules. These Controllers are CAN-enabled which allows you to daisy chain them together when used an AEM Programmable Engine Management System or most other CAN-enabled standalone programmable engine management systems. The 4-Channel Wideband Air/Fuel Controller delivers the greatest accuracy and potential for power when tuning air/fuel ratio since it reads AFR in every cylinder chamber individually. If you have a forced induction engine, you can still mount the sensors pre-turbo by including AEM’s Backpressure Compensation Kit (PN 30-2064).

Q: Do I still need to run my factory exhaust gas sensor if I have an AEM Wideband Air/Fuel Controller?
A: Maybe. If your vehicle’s Engine Management System uses the O2 sensor for fuel control and you cannot recalibrate its sensor signal to work with the wideband air/fuel ratio sensor, then you will need to retain the factory sensor.

If you are running a factory ECU then you will need to continue to send it the factory narrow-band signal or it will throw a Check Engine Light (CEL).

Additionally, on emission controlled vehicles in California you MUST retain the entire stock emission system for emissions legality.

Q: Will my nitrous oxide system damage the wideband air/fuel sensor?
A: Nitrous Oxide itself is not in any way harmful to a wideband air/fuel sensor. However, running excessively rich will shorten the sensor’s life and many nitrous systems run in this condition. In this way, nitrous oxide may shorten a wideband air/fuel sensor’s lifespan.
http://www.aemelectronics.com/faq.php?cID=3#149



Some examples of wideband oxygen sensors from AEM

http://www.aemelectronics.com/wideband- ... roller-36/



http://www.aemelectronics.com/wideband- ... -gauge-25/

[mynameisowen]

Good post Betek. Any ideas on prices for these bad boys?