Oxygen Sensor Location

DAVEGOYA

MEMBER
2001 ACURA MDX
6 CYL
4WD
AUTOMATIC
70,000 MILES

My car get scanned and they found a code PO135 and tell me to replace the oxygen sensor1 in bank 1. I bought the sensor and I want to do it my self. But I don't where is this sensor. I saw a few of this sensor in the motor. And I don't wich one I'm going to replace. If you can help me with a diagram. I can appreciate that. Thank you

5 Replies

RASMATAZ

MECHANIC
75,992 POSTS

B1S1 is on the exhaust pipe upstream from the catalytic converter. The other is on the C/Converter. Here is a guide t help walk you through the repair and the location of the oxygens sensors in the diagrams below.

https://www.2carpros.com/articles/how-to-replace-an-oxygen-sensor

Check out the diagrams (Below). Please let us know if you need anything else to get the problem fixed.

Images (Click to make bigger)

SPONSORED LINKS

Was this

answer

helpful?

Yes

No

+1

Monday, September 1st, 2008 AT 5:09 PM

KHLOW2008

MECHANIC
41,815 POSTS

Hi davegoya,

It is the primary sensor.

Was this

answer

helpful?

Yes

No

+10

Tuesday, September 2nd, 2008 AT 8:58 AM

HUNDRIVER

MEMBER
3 POSTS
2001 ACURA MDX
6 CYL
4WD
AUTOMATIC
115,000 MILES

I have replaced the original oxygen sensors, Denso, with non-OE sensors, Bosch. I cannot clear the CE nor the VTM-4 lights. I also cannot engage the VTM-4 system. On computer analysis, the DTC still indicate the O2 sensors. As an electrical engineer, I am somewhat confident I installed them correctly. The MDX runs fine with no apparent problems. I am confused. Please help.

Was this

answer

helpful?

Yes

No

Monday, April 13th, 2020 AT 6:18 PM (Merged)

JEREMIAH

MECHANIC
217 POSTS

Check to make sure that the correct sensors were installed in the right order. The primary is an air/fuel sensor and the secondary is the heated oxygen sensor. Two different sensors that are not interchangeable.

Was this

answer

helpful?

Yes

No

+1

Monday, April 13th, 2020 AT 6:18 PM (Merged)

HUNDRIVER

MEMBER
3 POSTS

They both are 4-wire sensors. Two wires in each are listed as a heater circuit. I have rechecked the color codes and signal wires between the OEM and bosch wire color coding. I have cleared the VTM light but not the CEL. I'm now getting P0135, P0141 and P0133, indicating oxygen sensor heater circuit. The MDX still runs fine. I am perplexed.