Can I get a diagram of the upstream and downstream O2 sensors?

2005 CHEVROLET MALIBU
250,000 MILES • 2.2L • 4 CYL • 2WD • AUTOMATIC
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RAIKIRIR2
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Can someone show me a detailed diagram of the upstream and downstream O2 sensors and where they plug in after installation?
Nov 8, 2023 at 8:39 AM
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JACOBANDNICKOLAS
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Hi,

There are two sensors. One is a pre-catalytic converter sensor (upstream) and the other is a post-catalytic converter sensor (downstream).

If you look at pic 1 below, I highlighted the upstream sensor and connector location. Note that the sensor is in the exhaust manifold and requires the removal of the exhaust manifold heat shield. Pics 2-7 are the directions for removing and replacing the upstream sensor.

If you look at pic 8 below, I highlighted the downstream sensor and connector. The remaining pictures are directions for the removal and installation of the downstream sensor.

Here is a link you may find helpful. It explains in general how it is done, and the pics are a little more helpful. LOL

https://www.2carpros.com/articles/how-to-replace-an-oxygen-sensor


Let me know if this helps or if you have other questions.

Take care,

joe

See pics below.
Nov 8, 2023 at 8:00 PM