The coils aren't even and odd, so you're on the right track. I'll bet if you were to drive it long enough like this, you'd eventually get a code for #3.... but don't try to find out.

 

Heck you can buy the OEM sensors (in a bosch aftermarket box) from amazon for less than that. I just bought a pair, and they have the land rover part number etched into the sensors, and the connectors are the correct colors, etc.

 

Oh thanks for letting me know this. I am going to call AB today and tell them there sensors they sold me are broken.

I assumed that.
I did buy the rear o2's from Amazon.

 

Did you check the female ends of the 02 connectors? I had some similar codes, and after messing around for weeks with new 02 sensors, I found one of the female connectors was slightly fouled, one of the four prongs was blackened. Cut and spliced a new one in, boom, fixed like 3-4 codes.

 

I also used the 02 from antlic British . And the guy the works on my disco said for what ever reason these 02 do not work right . So I took his advice and changed them out to oem 02 sensors to find a perfect smooth idle . He says he has tried them several times from Ab and talk to them and they do not no why they cause a bad idle . His thoughts are they are a standard 02 . Thery are even a different shape and style

 

After 80 miles of driving today here are the codes that have popped up again. I cleared the codes this morning.
Pending Trouble Codes:
P0300 Random/Multiple Cylinder Misfire Detected
P0303 Cylinder 3 Misfire Detected
P0305 Cylinder 5 Misfire Detected
P0161 O2 Sensor Heater Circuit Malfunction (Bank 2 Sensor 2)
Trouble Codes:
P1300 Boost Calibration Fault
P0303 Cylinder 3 Misfire Detected
P0305Cylinder 5 Misfire Detected
I find it interesting the computer thinks the 303 and 305 are both "pending" but also "hard" faults.
Still waiting on plug wires... I also am smelling a sweet smell of anti freeze, however when I smell my exhaust it doesn't smell sweet nor did it fail the head gasket block tester. Really wish the wires would get here sooner rather than later.

 

I did not check the ends of the o2's. I will do so.

Thanks for telling me. I ran out of day time to call them today. I will tell them whats going on and get a set from the dealer regardless.

 

I've heard some speculation that the reason that the left front o2 sensor fails (and is more difficult to remove) is that coolant from the throttle body heater leaking gets on that sensor. Not 100% on this, but you might look and see if it's leaking.

 

I could see how that would make it fail. It was leaking and I just replaced the gasket, all is good with the throttle body now.

 

I just did this today on my 99. It totally kicked my butt. I cut the connector off the old o2 and slipped a box end wrench over the sensor. I tried PB blaster soaking from the night before and this morning. I tried heat from a blow torch. There is just no really good way to get leverage on that guy. I finally got it to move maybe half a turn and it never got loose. It finally rounded off enough that I wasn't going to make any progress. I finally dropped the front cross-member and y-pipe (breaking on bolt on the front cross-member and have to cut two bolts on the y-pipe. Then I removed the top off of the sensor with a hammer and a saws-all and I hammered the next smallest size deep socket onto the sensor. It finally came out with a 1/2 drive air impact.

I had to get a tap to clean up the threads on the y-pipe because half of the ones from the sensor were still in the bung.