Hello,

I have a 2007 LR3 with 102,000 miles.

I had check engine light come on the other day and took it to LR shop to have checked out. It came back with the following codes:
-P0116-24 (Engine Coolant Temp Signal Stays High)
-P101-00 (Mass or Volume Air Flow Circuit Range Performance)
-P307-00 (Cylinder #7 Misfire Detected on Start Up)
-P0139 (Heated Oxygen Sensor Slow Response Bank 1 Sensor 2)
-P0172-00 System Too Rich Bank 1)
-P0420 Catalyst EFF Below Threshold Bank 1&2)

There were no vacuum leaks and mechanic thought misfire could be related to spark plugs needing replacement at 105k service. He replaced the Mass Airflow Sensor and reflashed the engine ECM.

The next day check engine light comes back on and I have the P0420 code again. Now they suggest replacing Catalytic Converter and Ox Sensor (x2) for a cost ~ $1,500.

My question is - if I'm mechanically minded, is this something that can be repaired by me? If so, any online info/instructions anywhere?

Thanks and any help appreciated!

 

P0420 is the cat efficiency for bank 1. (this is the passenger side cat.)
How much do you stand to save by doing this yourself?
It's not a difficult task although I dont think you really want to do this in your driveway on your back.
Remove 2 nuts at downpipe passenger side, Disconnect 2 ox sesnsor plugs, cut out catalytic converter, swap over or replace ox sensors, install new cat.
Clear ECU codes reset engine ECU adaptions. Roadtest to verify repair, recheck for codes.

 

Mike,

Thanks for the reply. I can buy the parts myself and save $1,000 - so, may be worth a little uncomfortable back ache.

 

Sorry, thought this was a Range Rover. On the Lr3 you will need to support the transmission and remove the crossmember then unbolt the r/s cat at the y-pipe and front muffler. Hose all the nuts and bolts at the flanges and crossmeber bolts down with penetrating oil before trying to remove them just in case they are rusted and frozen.

 

Hi Mike -- while on the topic-- forgive the sort of hijack..

part 1: Is there ANY truth to the claims that putting in new O2 sensors, when yours have not failed or throwing codes will improve mileage as claimed on roverparts web site.

Part 2: Any opinion on changing out brake lines... just curious on these vehicles with 100k+ miles on them.

cheers

 

The problem with trying to change ox sensors on these is that there is a good chance
they will come out 1 turn and stop, then you are left with the decision ..what to do next?? I would leave them alone until you get a fault. I'm not going to answer the fuel mileage claim, but if an ox sensor is operating properly, there is no need to replace it.

Land Rover recommends replacing the rubber brake hoses every 6 years, I think it's a good idea and try to upsell them.

I gonna take you up on your offer for diff parts, maybe we can do some kind of barter. I'll call you later today.

Cheers

 

Sounds good---

 

thats not a V6 is it, seen that a code a few times and we cured it with bg 44k and an induction flush.