# O2 sensor

**URL:** <https://community.cartalk.com/t/o2-sensor/91903>\
**Category:** Maintenance/Repairs\
**Created:** [December 8, 2015, 11:56am UTC](https://community.cartalk.com/t/o2-sensor/91903 "2015-12-08T11:56:42Z")\
**Posts on this page:** 5\
**Page:** 1

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**Author:** ![phantom\_lair](https://avatars.discourse-cdn.com/v4/letter/p/65b543/32.png) [@phantom\_lair](https://community.cartalk.com/u/phantom_lair)\
**Post date:** [December 8, 2015, 11:56am UTC](https://community.cartalk.com/t/o2-sensor/91903/1 "2015-12-08T11:56:42Z")

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I have a 06 chevy 3500 express van with a 6.0 engine.The engine light came on about the O2 sensor bank 1 sensor 1 and bank 2 sensor 1 came up on the on the scan tool. It run great. how do I fix it

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**Author:** ![bloody\_knuckles](https://avatars.discourse-cdn.com/v4/letter/b/ee7513/32.png) [@bloody\_knuckles](https://community.cartalk.com/u/bloody_knuckles)\
**Post date:** [December 8, 2015, 4:58pm UTC](https://community.cartalk.com/t/o2-sensor/91903/2 "2015-12-08T16:58:12Z")

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If your scan tool lets you see live data then run the engine and see if the O2 sensors voltages are low or zero. If they are then you have to replace the sensors. Depending on where they are located it may or may not be easy. When I did mine I purchased on O2 sensor tool that fits around the sensor and wire and allows you to use a breaker bar to crack it loose. If this is the first sensor change on your vehicle they may be stubborn and require some heat (torch) to loosen. Good luck!

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**Author:** ![system](https://global.discourse-cdn.com/cartalk/original/3X/1/d/1d47c66a543aa6c5a7873bb2320858f978ff52ed.png) [@system](https://community.cartalk.com/u/system)\
**Post date:** [December 8, 2015, 6:28pm UTC](https://community.cartalk.com/t/o2-sensor/91903/3 "2015-12-08T18:28:36Z")

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Impossible to tell how to fix it without the codes. There are lean codes that folks think are fixed by oxygen sensor replacement when it’s actually a leaking intake manifold. Or maybe it’s a bad MAF sensor, or a vacuum leak. Too many possibilities beside the O2 sensors. I would prefer to fix cars instead of throwing parts at them, so codes are VERY important.

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**Author:** ![Mustangman](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/mustangman/32/44130_2.png) [@Mustangman](https://community.cartalk.com/u/Mustangman)\
**Post date:** [December 8, 2015, 7:44pm UTC](https://community.cartalk.com/t/o2-sensor/91903/4 "2015-12-08T19:44:36Z")

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Which O2 sensor code?? Failed O2 sensor or failed O2 heater? A failed heater will throw a CEL but the truck will run just fine. Odd that BOTH sides failed at the same time but this is a common failure.

How do you fix it? Replace both sensors. If that doesn’t do it, the wiring is likely bad at some spot.

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**Author:** ![knfenimore](https://avatars.discourse-cdn.com/v4/letter/k/9fc348/32.png) [@knfenimore](https://community.cartalk.com/u/knfenimore)\
**Post date:** [December 9, 2015, 1:53am UTC](https://community.cartalk.com/t/o2-sensor/91903/5 "2015-12-09T01:53:36Z")

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Squirt the O2 sensors with PB Blaster and let it sit overnight. They should come right out then.