Codes P0141 and P0135?

2007 MERCURY MILAN

195,000 MILES • 2.3L • 4 CYL • 2WD • AUTOMATIC

LIONELL8732

MEMBER
150 POSTS

I'm getting two troubles codes and would like to know how to fix them, they are P0141 and P0135. I went to the part store and got a brand-new downstream sensor, and these two codes keep popping up. I check the wiring on both oxygen sensor connectors and see no tears or rips. Am so lost.

Sep 23, 2023 at 2:33 PM

JACOBANDNICKOLAS

✓ASE Certified Mechanic
110,193 POSTS

Hi,

The codes are both related to the oxygen sensors, as I believe you already know. The thing is, the downstream code (P0141) is likely the result of the P0135.

The possible causes are broad. The only way to determine the issue is to go through the diagnostics provided by the manufacturer. They are extensive, but that doesn't mean you will need to complete all of them. LOL, You may find the cause within the first few tests.

I attached all the diagnostics below. Take a look through them and let me know if you are comfortable performing them.

Let me know.

Joe

See pics below.

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Sep 23, 2023 at 8:35 PM

Repair Safety Notice: This information is for general instructional purposes only. Vehicle repair can be dangerous. Verify all information, follow manufacturer service procedures, use proper tools and safety equipment, and consult a qualified repair shop when needed.