Hey everyone...

2003 LR Discovery w/ 4.6 with 107,000 miles....CEL came on last week with the following codes thrown and screened by Autozone......P0154 (oxygen circuit, no activity bank 2) P0174 (Bank 2 system too lean) P1415 (no info) and P1174 (no info)

Engine has a rough idle (500-700 rpms) but does not stall out. I see a lot of posts about O2 sensors and also plugs and wires. Any direction and/or help is greatly appreciated

Cheers,

Jay

 

replace your upstream O2 sensors. clear the codes and go for a drive.

 

+1 - upstream o2 sensors are adjusting your fueling. Rough idle and throwing an o2 code it'd be the first thing I swapped.

Dave

 

easy.
O2 sensor on passengers's side.
Front one - pull it out.
Replace it with BOSCH only.
Get on on amazon about $65.
Clear all codes.
and drive.

 

Thanks again....will try and update asap...

 

Quick update - swapped out front O2 sensor and problem appears to be solved. Runs much smoother and codes cleared. Thanks again for everyone's assistance.

My friend has the same model with only 67,000 miles on his. He just replaced the exhaust from cats back. Now he is receiving a 0420 code. Is that the rear o2 sensor?