O2 Sensor codes...

[fuel451]

Getting the following codes regarding O2 sensors and would like to know what the recommended replacement part numbers for each is. Atlantic British has a pretty wide variety of O2 sensors to choose from. Have a 2002 RR HSE with about 116K miles. Not that this has any bearing on the codes, but I recently had all plugs, MAF sensor, and water pump replaced by a certified mechanic.

P0133 (O2 Sensor CKT Slow Response (Bank 1, Sensor 1)
P0155 (O2 Sensor Heater Circuit Malfunction (Bank 2, Sensor 1)
P0420 (Catalyst Efficiency Below Threshold (Bank 1)

Pulled the codes with an Actron CP9175 OBDII Reader. Also, I don't consider myself a mechanic, but I do have the workshop manual and I'm pretty technically inclined. Is this something that can be done by myself or is it recommended that I take it to a mechanic.

 

[joey]

Personally I would clear the codes and drive for a bit and see if they come back or stay gone...

 

[fuel451]

Thanks for the input. Originally there was only the P0155 code and I cleared it. After about two weeks and close to 200 miles, the three codes came up.

I can't verify whether or not the sensors have been changed, but considering the oil change sticker had 13K miles less than the odometer, I'm going with no on the sensors.

Amazingly enough, the A/C is frost and the truck runs very smooth. Definitely a keeper.

This is probably an easy question, but when referring to the banks and sensors, which is which? The Workshop manual only lists them as Pre-Catalyst and Main Catalyst, left and right respectively.

 

[joey]

Bank 1 = Drivers side
Bank 2 = Passenger

This below should help with a few other questions that may come up.

http://www.roverparts.com/TechTips/#rangerover

 

[RR06 hse warrior]

I’m getting p0133 and p0155 codes already changed all 4 sensors. Initially was getting o2 sensor not ready for emissions but no CEL. Only after changing sensors did I get the CEL but now the emissions oxygen sensor monitor shows ok or complete. Any suggestions ?

 

[RR06 hse warrior]

I’m going to change the MAF next. Took to a local shop and not much help. Only suggested new MAF Sensor or put old sensors back. But that will still not fix the original o2 sensor monitor problem for smog/emissions.

 

[joey]

Clean the MAF sensor and make sure the airbox is closed, and use a paper filter not a K&N oil type.

 

[RR06 hse warrior]

Replaced MAF and checked air box hopefully it will work and light doesn’t pop up again

 

[RR06 hse warrior]

Just an update. I changed the MAF and the throttle body and ended putting the old upstream O2 sensors back in. I think I got bad O2 sensors even though they were OE denso. Well it passed smog so that was the problem all along. Hope this helps someone.

 

[RR06 hse warrior]

Also, I did clean the O2 sensors before putting back in with throttle body/ sensor cleaner..