O-2 Sensor Question

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Jul 11, 2002 | 02:13 PM

CptMorgan

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From: Vancouver BC

O-2 Sensor Question

How often should an O2 sensor be changed? What are the signs of a bad O2?

Jul 11, 2002 | 02:16 PM

scorp508

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From: Boston, MA

I honestly don't know of an "interval". The signs of one could be some loss of power and definitley lower gas mileage.

Jul 11, 2002 | 02:38 PM

CptMorgan

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Re: O-2 Sensor Question (CptMorgan)

My vette has 80,000 miles on it and I don't know if the O2 has ever been changed. I'm sure it hasn't been changed in the last 35,000 miles.

Jul 11, 2002 | 02:40 PM

scorp508

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From: Boston, MA

I would change it then just to be sure and get a starting point.

Jul 11, 2002 | 03:07 PM

C4-Wolf

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From: NYC NY

Re: (scorp508)

If you've notice your average mpg going down, or you feel that it is low right now, it might be time. Many people get 18+mpg for pretty much city driven cars.

Jul 11, 2002 | 03:14 PM

kaiser

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From: des plaines, il

Re: O-2 Sensor Question (CptMorgan)

Basic info on O2 sensors here:

http://www.parttrackers.com/library/1/

Section 3.03.

Jul 11, 2002 | 03:30 PM

pascualjr

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From: Mililani HI

Re: O-2 Sensor Question (CptMorgan)

I changed mine at about 105k. I started getting lousy mileage - 13-15 mpg. Now it's back to the normal 18-20 mpg. :seeya

Jul 11, 2002 | 03:43 PM

65Z01

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From: SE NY

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Re: O-2 Sensor Question (CptMorgan)

Use a paper clip to jumper ALDL pins A&B, start the engine and wait until the SES flash rate drops to about 1HZ. Then the On/Off duration indicates rich/lean condition. Rev the engine to about 2,000rpm, hold for a copla seconds and notice the SES flashes.

If the SES On/Off durations are about equal and about 1Hz the ECM is in closed loop mods and the O2 sensor is fine.

Of course a scan tool is the easy way to see.