O2 sensors?

BRNFRRST

MEMBER
2001 OLDSMOBILE AURORA
V8
2WD
AUTOMATIC
75,000 MILES

My check engine light came on and had an Auto Zone employee put a computer on my car to see what caused the light to come on, it read O2 sensor issue. I replaced 2 sensors, and still have problems, I went back to Auto zone and he now tells me I have 3 to 4 O2 sensors, can you tell me how many and where they are. I also now get other readings that saya MAP sensor, MAf sensor, Pedal Throttle Position sensor, and Knock sensor. It is driving a little better, but feels like the throttle is stuck open when driving down the highway.

3 Replies

ERNEST CLARK

MECHANIC
1,730 POSTS

You have 3 O2 sensors on your vehicle. One on each side of the cylinders before the catalytic converters, and one on each exhaust pipe after the catalytic converters.

Also, it is very unusual for all of those sensors to go bad at the same time. This hints at the possibility that your computer is faulty, or the wiring harness to the computer has some bad/corroded connections.

Your powertrain control module is located under the hood, right next to the brake master cylinder. I don't suggest that you mess with that thing yourself. (Unless you are an A.S.E. Certified mechanic)

If AutoZone can't tell you more about the possibility of you computer being faulty, go to a competent mechanic. Their computers are much more sophisticated, and they'll usually do a free estimate.

Here is a guide to help walk you through the replacement and diagrams below to show you the oxygen sensor location for your car below.

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

Check out the diagrams (Below). Please let us know if you need anything else to get the problem fixed.

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