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o2 sensors 1 wire to a 4 wire

I love my Chevy Chevette!
Posts: 2
Joined: 11/12
Posted: 11/26/12 12:32 AM

Do anyone have an idea how wire a one wire o2 sensor in to a 4 wire , i was told from a tech that my o2 is not getting hot enough in my headers for the computre to read what to do. So if I could get some i really appreciate it,i know i got alot going on that's wrong. Thks.  

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I have an SS396 tatoo
Posts: 448
Joined: 03/12
Posted: 11/26/12 09:31 AM

first... identify the oxygen sensor is a Narrow band not a wide band sensor...  

the same wire hooks to the ECM...

you will have 2 ground wires...  and one heater wire.. that needs power.. usually from the IGN 1 circuit.. same as the ignition system

the trick is to have the sensors hooked to a really good engine ground...  

in OEM installations.. the ground side of the SENSOR circuit is grounded to a specific terminal on the ECM connector...    so you might want to be sure that where you ground them to probably the back of the cylinder head is a good ground connection..

the 4 wire heater circuit in OEM installations is grounded to the engine...

in a 1 wire sensor.. the shell is grounded... so half its circuit is up through the exhaust system to the engine and then to the ECM ground..

in a 2 wire sensor...  they have an independent ground that is usually connected to the engine block...

in a 3 wire sensor..    the ground is shared by a single wire by both the heater element and the sensor..  this caused all kinds of trouble when the ground went bad... i have seen 1.5 volts on the oxygen sensor circuit with a scan tool...  as the heater was trying to ground through the sensor circuit..  other than that.. 3 wire sensors work just fine...

i hope this explains how it works...

please be careful to NOT run voltage through the sensor circuit.. only the heater circuit..

please be sure that your grounds are properly made..  

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