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O2 sensor question

Question: I took my Subaru to get smogged. Didn’t pass the said up stream o2 sensor. So I replaced it and took back in for smog. Didn’t pass again same problem

Another case of shooting the messenger, Your o2 sensor was probably working correctly and telling you that there is a problem with the engine.

We need the code(s) that the o2 sensor is giving. P0XXX

Replace B1 S1 O2 sensor so ECU monitors will run. That’s I have here

If you’re not in Calfornia or Hawaii you need to get a parts store such as AutoZone to do a quick scan and provide you the exact code.

As you have discovered, setting an O2 code does not mean the problem is the O2 sensor.

The vehicle probably hasn’t been driven enough to reset the readiness monitors.

Until that’s done, the vehicle won’t pass the emission test.

https://repairpal.com/how-to-perform-a-basic-drive-cycle

Tester

Code P0065

I drove it 30 miles

Tester

Model , year, and engine of your Subaru? P0065 isn’t an O2 sensor code.

Well there you have it, blocked hose, bad valve, or get the computer reflashed. But at least you got a new sensor out of the deal.

Ya got new valve, hoses are good. Now to see how much to flash computer. Thank you everyone