P0031 code doesnt GO Away after O2 replacement...HELP !!!

[trdsport]

Hey folks
Had a P0031 code, bank1 sensor 1, it was one heck of a job to reach it with a wrench, as i didnt want to buy the special socket ($15 or so),cut the wire harness at the sensor for the socket, cut a 22mm long socket to desired size & removed the sensor. Put a New denso sensor &connected to harness, CODE still doesnt go away. any thoughts.

 

[Warwicke36]

Hey folks
Had a P0031 code, bank1 sensor 1, it was one heck of a job to reach it with a wrench, as i didnt want to buy the special socket ($15 or so),cut the wire harness at the sensor for the socket, cut a 22mm long socket to desired size & removed the sensor. Put a New denso sensor &connected to harness, CODE still doesnt go away. any thoughts.

Check the O2 heater circuit for power and ground. Likely a short in the wiring somewhere. If either isnt spec.... Follow the harness and check for pinched or chaffed wiring. To potential for hot exhaust to melt wire insulation is possible too. Good luck. Report back!

 

[4RunnerAquasport]

Also have been reports of Bootleg Denso parts in recent years. They really look good. Where did you buy the sensor?

 

[trdsport]

Bought from Rockauto, oh i did rust spray the frame area same time, i did realise some oil sprayed on the harness...could that be a reason.?

 

[trdsport]

If testing the leads at harness what voltage am i looking for..Thnks