I love my Chevy Chevette!
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.
I have an SS396 tatoo
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..