Dlee5298

I have a 2005 civic ex with a p0134 code. Which says its air/fuel ratio sensor. I understand from reading other people's posts that it is a o2 sensor. Confused on which one that is, I only see 2: One under the hood and one in the middle of the cat. converter. I have read posts that its upstream or downstream just not sure which one. I have done heat test on both, the one in converter seem to be bad (no reading). Could it be this one? Thanks for any help on this.

ezone

It is an A/F sensor. NOT an O2 sensor.

Looks the same, does a similar job, but electrically operates completely different. Not swappable.

Anyway, it is the one closest to the engine. The one sticking out of the first exhaust pipe, not the one stuck in the side of the cat.


Use a DENSO sensor if that is what comes out of it. Look on the old one for the brand and maybe the part number..

Dlee5298

Thanks ezone. Since it is the a/f sensor is that why it is so expensive? Found one at advance for $280, will this sensor take the code off? or do you think I should take to a mechanic to make sure before spending that much on something that may not fix the problem? Thanks again.

ezone

No. It is bad.
Most people can't evaluate these sensors anyway, you must rely on the software to make the judgement.

The code will be fixed with the correct sensor.
Pretty easy DIY to replace it.
7/8" wrench and one connector.

The problems happen when someone cries that it is too expensive and they try to go cheap on the sensor.....THEN the huge problems start.



The correct sensor is not expensive; Wrong sensors will be incredibly expensive, no matter how cheap you think you can find them.



I don't care HOW CHEAP you can find WRONG sensors, that is completely irrelevant.



Do you really think I am psychic? Jeez. I have no way of knowing if your Advance parts are right or wrong. I can't see a damn thing.

CLUE: Aftermarket parts stores may have OEM parts reboxed in their own brand packaging. You have to open them up and look for yourself.
Most cheapo parts place flunkies won't have a clue nor a care.

Open the box and see what brand name is on the side of the sensor, and the numbers stamped on the side of the sensor.
If it isn't a DENSO, then walk away.
If it IS a DENSO sensor, then google the part number stamped on the side of the sensor (NOT the one on the box).
The DENSO website will have part numbers and applications. Look it up yourself ahead of time.