Just over 146K I got an O2 Sensor code and decided since I had no service records I would replace all of them. Used the OEM fit Bosch sensors, Life was good no more codes.
I Then got a P0304 about 30 miles later so I changed the spark plugs, no more code. About 600 miles later I got a P0130 and P0171 so I thought I got a bad 02 sensor.
Replaced the upstream bank 1 sensor life was good again. About 1500 miles later got a P0130 again and a little rough idle and heard the spark crack under the hood so I changed the spark plug wires to Kingsborne 8MM engine smoothed out, crack sound gone. P0130 kept returning so I replaced the Bank 1 upstream sensor again thinking maybe it got fouled by the misfire.
Life was good again until yesterday at about 800 miles after the last change I got a P0130 again. The connector did not look oily but I cleaned it with electrical cleaner and a Q-tip and reapplied dialectic grease. After about 8 miles P0130 is pending again.
I am loosing coolant, when I purchased the vehicle 10 months ago I did the head gasket test using the liquid that changes color and it was negative. I had changed all the hoses, radiator and water pump while doing the inline thermostat conversion. I was thinking head gasket until I noticed a few drops of coolant on the sub frame when I was changing the O2 sensor. Have not been able to locate the source of the coolant, I put dye in the system but the light I have sucks and I need a better one.
After reading everything I could find on the forum, no one I could find had the head gaskets as the problem.
I am thinking of swapping the O2 sensors side to side to see if it throws a bank 2 code. Need to run another head gasket test, but it does not appear to be over pressurizing the cooling system, because it is not spraying coolant out the overflow.
Anyone had a problem like this?

 

Use
http://enginecodemaster.com

to diagnose Land Rover OBD codes.

Engine Code master Rover Section was created from codes in the Rave manual. Not from generic.

 

Yes I had the exact same issue, except even more codes related to the O2 sensors. It turns out, even using Bosch, sometimes the O2 sensors were bad on arrival. I put a second set of O2s and that problem resolved. Then I started throwing codes 0171/0174...those are typically related to MAF issues (or vacuum leak). But since you have new O2 sensors, maybe the MAF is old and needs to be replaced. I replaced my MAF and the truck is running a lot stronger. From what I understand as these two seperate components wear, sometimes replacing one makes the ECU realize the other component needs replacing. Just my two cents...