4-wire O2 with OBD-0
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From: Va BiOtch, VA, USA
4-wire O2 with OBD-0
I know that this has been done before, but I have one question. The 1-wire O2 sensors(OBD-0) give off a voltage of .1v-.9v right? and the wideband 4-wire O2 sensor ranges from something like 2v-6v? how does this work if the OBD-0 ECU is expecting voltages between .1v-.9v from the O2 sensor?
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From: Dandridge, TN, USA
Re: 4-wire O2 with OBD-0 (See Are X)
i ran across this somewhere...
3. A 4-wire O2 sensor must be added. In order to do this, 3 lines must be added to the harness. One line runs from the O2 sensor plug to the 8 wire plug mentioned in #1, this wire is yel/blk. The second line is a grn/wht line that runs from the O2 sensor plug to any location on the grn/wht wire on the OBD0 harness. The third line is an org/blk line that leads to the ECU. The final wire is the white one. This wire serves the same purpose on both the OBD0 and OBD1 cars. This white wire is the O2 sensor wire itself…on the OBD0 engine harness, it is a single wire and has a rather large plug on it. This plug must be cut off and the white wire for the OBD1 plug soldered on.
does this help?
3. A 4-wire O2 sensor must be added. In order to do this, 3 lines must be added to the harness. One line runs from the O2 sensor plug to the 8 wire plug mentioned in #1, this wire is yel/blk. The second line is a grn/wht line that runs from the O2 sensor plug to any location on the grn/wht wire on the OBD0 harness. The third line is an org/blk line that leads to the ECU. The final wire is the white one. This wire serves the same purpose on both the OBD0 and OBD1 cars. This white wire is the O2 sensor wire itself…on the OBD0 engine harness, it is a single wire and has a rather large plug on it. This plug must be cut off and the white wire for the OBD1 plug soldered on.
does this help?
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From: Atlanta, GA, USA
Re: 4-wire O2 with OBD-0 (Jeff C)
4-wire O2 is NOT a wideband O2.
The 4 wires are for two circuits; one is the actual sensor and the other is the heater.
Only the Vtec-E motors have a wideband O2 so the ecu can monitor the leaner burning motors.
A wide band O2 has more wires.........
The 4 wires are for two circuits; one is the actual sensor and the other is the heater.
Only the Vtec-E motors have a wideband O2 so the ecu can monitor the leaner burning motors.
A wide band O2 has more wires.........
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From: Milky Way
Re: 4-wire O2 with OBD-0 (See Are X)
Yes
The four wire is just a one wire with a 12 volt heater added (2 wires) and an electrically isolated sense cell (other 2 wires). This set up helps with noise immunity, and the heater lets the sensor light off in about 20 seconds instead of 2 to 3 minutes. The response times are a little different, but lets not get lost in subtleties.
On the one wire the sense cell positive is brought out with the wire, and the negative is grounded to the sensor shell. As you might imagine, the exhaust pipe is not the best of electrical connections for such a low level signal going back to the ECM hence the evolution to the four wire.
Regards,
BigMoose
The four wire is just a one wire with a 12 volt heater added (2 wires) and an electrically isolated sense cell (other 2 wires). This set up helps with noise immunity, and the heater lets the sensor light off in about 20 seconds instead of 2 to 3 minutes. The response times are a little different, but lets not get lost in subtleties.
On the one wire the sense cell positive is brought out with the wire, and the negative is grounded to the sensor shell. As you might imagine, the exhaust pipe is not the best of electrical connections for such a low level signal going back to the ECM hence the evolution to the four wire.
Regards,
BigMoose
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efking1985
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