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Narrow Band vs Wide Band O2 Sensor

V-6 Camaros rule!
Posts: 105
Joined: 04/09
Posted: 02/01/13 12:06 PM

Sorry I haven't much time to sit here researching all the posts etc so I am going this route. Who among you out there have replaced your O2 Sensor from the Stock Narrow Band Single Wire unit to the 3 or 4 wire Wide Band O2 Sensor? Please feel free to fill me in on all of your findings. I already know a Wide Band is preferred over the Narrow Band. My engine is not stock & has a brand new Block and all internal parts etc for those of you who aren't familiar with my 1987 Corvette. I have Shorty Header's currently & due to financial restraints going back to the Factory Exhaust Manifold set-up for a short foreseeable future. Then onto Long Tube Header's. Any information from those who have made this switch, even on stock manifolds, is greatly/interestingly appreciated. And, those with Long Tube Header's feel free to chime in also. Thank you.  
Gregorio Lonewolf

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My first time was in a Chevy
Posts: 241
Joined: 04/12
Posted: 02/02/13 05:24 AM

replace your O2 Sensor from the Stock Narrow Band Single Wire unit to the 3 or 4 wire Wide Band O2 Sensor?      NOT!!!!!!

you can replace your single wire narrow band unit with a 3 wire narrow band unit from an early 90s gm application...  as the additional 2 wires are for the oxygen sensor heater... this is used to bring the oxygen sensor to operating temp earlier and when using mid length and long tube headers...

with narrow band 4 wire oxygen sensors used on early OBD2 applications... the additional and sensor only ground wire is just grounded to the computer directly... its just more complicated to connect... since most headers should be decently grounded to the cylinder heads through the header bolts.... ceramic coated headers might have issues and require either a ground stud or a 4 wire narrow band sensor to keep the fractional voltages less than a volt going to the computer..

there are wide band 4 and 5 wire sensors.. along with additional types...
these require a totally different computer designed to work with them..  some have power running to the sensor and it changes the voltage back to the computer on the signal wire...

here is some info from the bosch oxygen sensor tech page

Purpose and Function.
Oxygen Sensors are used to detect the amount of excess oxygen in the
exhaust gas after combustion to indicate the relative richness or leanness
of mixture composition.
The oxygen sensor contains two porous platinum electrodes with a
ceramic electrolyte between them. It compares exhaust gas oxygen
levels to atmospheric oxygen and produces a voltage in relation to this.
The voltage produced by the oxygen sensor will be typically as small as
100 mV [lean] up to a maximum of 900 mV [rich]. An active oxygen sensor
would cycle between these two points as the engine management
system drives the mixture rich and lean to achieve an average sensor
voltage of ~465mV. This would represent the mixture ratio of 14.7:1.
This type of operation is normal for a “narrow band” style of sensor;
these are used for the majority of standard vehicle applications.
Bosch also produces “lean” sensors [type code LSM11] for testing
applications, these provided a broader operational range by extending the
lean scale, a detailed curve can be seen below. These sensors are not
recommended for standard vehicle use.

The introduction of “Planar” manufacturing technology has allowed
Bosch to produce a “wide band” oxygen sensor that has an extended
mixture operating range [type code LSU4]. These sensors operate on a
completely different principle to the standard “thimble” type sensor
manufactured by Bosch. The operation of this type of sensor requires
various software controls to manage oxygen cell current requirements,
signal interpretation and heater management. Bosch produces these sensors
for use with our engine management systems that are developed in
conjunction with individual vehicle manufacturers.
It should be noted that these sensors require a complex heater
management system in order to maintain sensor accuracy across
various operating conditions. Sensors not operated in conjunction with
an appropriate heater management strategy may be damaged due to
thermal stress. Consultation with the engine management system provider
should take place prior to use of these sensors to ensure they are supported.

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