# O2 sensor voltage

**URL:** <https://forums.speedlife.net/t/o2-sensor-voltage/37120>\
**Category:** NYSpeed Automotive\
**Created:** [October 17, 2007, 5:32am UTC](https://forums.speedlife.net/t/o2-sensor-voltage/37120 "2007-10-17T05:32:08Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![timo](https://avatars.discourse-cdn.com/v4/letter/t/c4cdca/32.png) [@timo](https://forums.speedlife.net/u/timo)\
**Post date:** [October 17, 2007, 5:32am UTC](https://forums.speedlife.net/t/o2-sensor-voltage/37120/1 "2007-10-17T05:32:08Z")

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Have a '97 Ford Aspire with check engine light on. Also, unfortunately has an overdue inspection. Recent scan tells that downstream (after CAT) 02 sensor has problem. Best price for a new one is over $260, and for this car it hardly seems worth it.  
As a fix was thinking I could feed a constant voltage into the ECU from that wiring. Anybody think that would work? Would that keep that fault code from triggering? If so what voltage would I need, and is impedance important?

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**Author:** ![jetta4life](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/jetta4life/32/7368_2.png) [@jetta4life](https://forums.speedlife.net/u/jetta4life)\
**Post date:** [November 15, 2007, 10:28pm UTC](https://forums.speedlife.net/t/o2-sensor-voltage/37120/2 "2007-11-15T22:28:25Z")

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im sorry i dont have a useful response. i cant belive you bought that car…:rx3:

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**Author:** ![system](https://canada1.discourse-cdn.com/flex034/uploads/speedlife/original/2X/b/b7170c8eddc0b95ece6b88172b2f416a08489a45.png) [@system](https://forums.speedlife.net/u/system)\
**Post date:** [November 16, 2007, 11:35am UTC](https://forums.speedlife.net/t/o2-sensor-voltage/37120/3 "2007-11-16T11:35:52Z")

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[quote=“timo”"]

Have a '97 Ford Aspire with check engine light on. Also, unfortunately has an overdue inspection. Recent scan tells that downstream (after CAT) 02 sensor has problem. Best price for a new one is over $260, and for this car it hardly seems worth it.  
As a fix was thinking I could feed a constant voltage into the ECU from that wiring. Anybody think that would work? Would that keep that fault code from triggering? If so what voltage would I need, and is impedance important?

[/quote]

$252.21 at Carquest…and no feeding a constant voltage to the PCM will not work. The signal has to vary from 0-5volts