O2 sensor question

[mtbmaniac]

I have an 04' impreza wagon, I took my car in and the diagnosis is that my front O2 sensor is bad and needs to be replaced, and the shop wants $400 dollars to do it. They said that they need to replace the sensor as well as reprogram the ECU. Does anyone know why the it would need to be reprogrammed and I can't just swap the O2 sensor myself.

[freakray]

Sounds fishy to me. Replace the sensor yourself.

[wardak33]

well it depends...how many o2 sensors do you have? if they are willing to do all of them and reprogram the ECU..then thats a good deal. but what i don't get is why u have to reprogram the ECU. but if you know how to, replace them yourself. o2 sensors cost around $30-50 a piece.

[mtbmaniac]

I did some more calling around and got a quote for $300. it is only for the front O2 sensor before the cat. I could buy the sensor from autozone for $172, but the reprogramming part is the thing i don't understand. Will O2 sensors typically come out without the use of heating on a newer vehicle like this?

[Jay!]

This is on an N/A car, right? If so, it's pretty simple...

1: Unbolt headers from car
2: Unplug O2 sensor
3: Unbolt headers from cat
4: Remove O2 sensor

5-8: Reverse to install

[P&L Motorsports]

I believe their "ECU reprogramming" will be disconnecting the battery to reset it and clear the CEL.

[wardak33]

let me ask you this question...do you at all race/streetrace or have "fun" with your car???

[slideways...]

subarus have that self-learning ECU software dealy-O, so heres how you reset your ECU. after the sensor replacement unplug the battery for 10 minutes or whatever, then go beat on your car for 10 minutes. or if you drive like a granny, go take your car through a bunch of driving situations you see every day. you might get a bit of rough driving/gas mileage differences until the ECU can relearn your driving style. other than your CEL, thats all the resetting you need. to clear a CEL, find someone with a scan tool, or tell autozone to do it.