Cost to replace an oxygen sensor

Autozone will read the codes for free. $50 is a ripoff. Your car is out of warranty?

 

The oxygen sensor is covered by the emissions warranty. If your warranty has expired, then MSRP for the sensor is $207 for sensor #1 and $139 for sensor #2.
DiscountToyotaParts

Do you know what DTC had been logged?

 

it's pretty standard for them to charge a half hour to read a code- that's typically between $40 and $50.

if you've got the code, they can use the repair manual to diagnose. the thing about the prius is that not all hybrid specific codes are readable in a standard obd2 reader. and they want the money for doing the job instead of letting you get it done for free...

just wanted to clarify about emissions warranty... most emission related stuff is covered for 2 years/24k miles, but only the big stuff (cat, ecu, obd) would be covered for the 8 years/80k interval.

my sis just graduated from cmu last month. i take it you're a student there?

 

You mean alumnus, or possibly alumna, no?

 

If the Tacoma is a 1998 model, it probably has two oxygen sensors. The purpose of the first one is to provide feedback to the engine computer for purposes of adjusting air/fuel mixture. The purpose of the second sensor is to assess whether the catalytic converter is doing its job.

In your case, you haven't mentioned how many miles are on the odometer. If you have more than 100K, it is not surprising that you need a new sensor. Also the Prius engine ECU may be more sensitive in declaring an oxygen sensor failure compared to older vehicle ECUs.

BTW the 2G first sensor is an air-fuel ratio sensor, which is supposed to be more sensitive compared to an oxygen sensor. The 2G second sensor is an oxygen sensor. This is why the first sensor costs much more compared to the second.

 

Hey Patrick,

When did you change your O2 sensors? How many miles? And did you do it because your mileage was declining? If so, was there a difference in mpg when you changed it? I have 113k on my 05 and it is still peforming just as well as it was new. Thanks.

 

My 2004 has 58K miles and I have not yet had occasion to change the oxygen sensors. If no warning lights have appeared and your mpg is the same as when new, then no worries.

At your odometer reading, I would suggest that you consider replacing the iridium spark plugs, the engine and inverter coolants, the PCV valve, and the transaxle fluid, if these services have not yet been performed.

 

I'm currently at a dealership having my THIRD oxygen sensor replaced. The first two were under warranty and this one will set me back about $400... actually after a little haggling they are "good willing" the third one (paying for it). Phew. But it's obviously something to watch out for.

BTW, they said that there are 4 oxygen sensors in the vehicle and the test is to indicate which one it is, exactly.

Joe

 

Prius has two sensors. One is upstream of the catalytic converter and the other is downstream. The upstream one provides feedback to the engine ECU so that the engine ECU can adjust the fuel/air mixture, while the downstream one provides info to the engine ECU regarding the catalytic converter's performance.

If you have needed multiple oxygen sensors to be replaced, I am wondering if there's something about the fuel you are using that is contaminating the sensors.

A vehicle with a V-engine (like a V6 or V8) would have four oxygen sensors, two for each exhaust bank.

 

CMUCasey -

I have replaced two Oxygen sensors. One on my BMW and on my Toyota Sequoia. At least on those two cars it was a very easy job that took ~20 minutes. I bought OEM exact replacements on Amazon.com.

The aft senor for a 2005 Prius is listed on Amazon as:

Bosch 15621 Oxygen Sensor, OE Type Fitment

Link:
http://www.amazon.com/dp/product/B000VAZGTO?tag=priuschatcom-20 your homework and be sure that you buy the correct sensor.

(I also bought a code reader from Amazon.com. Having access to code reader is extremely helpful.)