O2 sensor failed?

techiedork

New Member
Hi all,

I have a 2005 Civic EX that returned a fault code: P0134: O2 Sensor Circuit No Activity Detected (Bank 1 Sensor 1)

From what I have read, it sounds like replacing the upstream sensor should solve the problem.

Has anyone here replaced the primary O2 sensor? If so, can you let me know what brand and model # sensor you recommend? I am looking at the Denso and NGK, but they are both fairly pricey. I know Bosch and several other aftermarket companies make them as well, but I don't want to cause further problems with a bad sensor and if I don't have to worry about splicing, that would be best.

Any advice you have would be greatly appreciated. Also, if anyone has any photos or instructions on how to complete the job (not sure if anything has to be removed to gain access to the sensor or if the car needs to be jacked up to get to it).

Thank you!!!

-David
 

00siboy

lurkin...
Registered VIP
Depending on which engine you have, its location is either on top of the manifold like the first pic, or down near the oil pan like the second pic. Denso is OE, NGK is fine too. I would only go with either of those. A non-OE brand can cause future fault codes.
EDIT: You will need a special socket to remove the sensor, or an O2 wrench.

 


lowlife9

New Member
Registered VIP
5+ Year Member
only use NTK or DENSO i recently replaced mine with a denso direct oem plug in which i purchased from autozone for 90 dollars the part number was 234-9005.
 

RadarMan

New Member
2004 Civic EX Coupe o2 sensor

Hello,

I'm new to this forum and found this post. I have the same problem on my 2004 Civic EX coupe. However, the sensor looks like its just been replaced and, if I had to guess, would say it probably an OEM unit. The connector on the sensor looks clean with no signs of splices.

My question is this. Is there some way to get a volt meter in the connector wires to make sure the unit is getting power? If so , which wires are for voltage, ground, and signal. Is there a fuse or relay that could be bad?

These things are expensive and I don't want to buy another only for find the old sensor was fine and something else is wrong.

Thanks in advance!

Eric
 


RadarMan

New Member
The CEL light is on. I had it checked at Advance but didn't get the code number. How ever the error message said "No response at all" for sensor 1 bank 1.

I hope that helps.
 

RonJ

Banned
Get the code and post it.

No response may refer to the O2 sensor signal sent to the ECU. The only voltage the O2 sensor receives is for the heater element, which may not be relevant to the code thrown. Post the code.
 

RonJ

Banned
After you post the code, reset the ECU to clear the code to see whether it returns. You don't want to concern yourself with a code that does not repeat after an ECU reset.
 

RadarMan

New Member
The code is P0134. The ECU was reset earlier in the day yesterday by my mechanic. I took the car in for inspection. Here in WV, we don't have emissions testing so this wasn't an inspection issue. Since the sensor looked now they recommended the reset which I agreed. But before I got out of the driveway of the shop the CEL came back on. So....of to Advance Auto to check.
 

RadarMan

New Member
Here is a bit more info.

I disconnected the four wire connector to the sensor while the car was off to prepare to measure voltage's on the harness end of the connector. I started the car and found that two of the wire were Vbat and gnd. Presumably these are for the heater circuit. The other two wires, in opposite corners of each other (red) measured 2.08V and the other (green) measured 3.2V.

Based on a youtube video for a wideband A/F sensor like this one, the signal voltages should be 3.0 and 3.3V. In other words, the 2.08V concerns me just a bit. Could something be wrong with my ECM?

Thoughts?????
 

RadarMan

New Member
Hello All,

Just wanted to let you know that I replaced the sensor today and all is not well. No more CEL!

Thanks!
 


Top