Cats or Lambda Sensors?
 

Few months ago I started getting:

16804 - catalyst system bank 1 efficiency below threshold p420
16814 - catalyst system bank 2 efficiency below threshold p430

I've ignored it for a few months thinking its the cats that gonna need replacing but now after driving the car some more and resetting the codes I'm getting:

P0134 oxygen sensor B1 S1 No activity
P1116 - Oxygen sensor heating B1 S1 Open circuit.

Could it have been the sensors slowly failing instead of the cats? I'm obviously thinking of replacing the both lambda sensors now :Confused:

Interesting. I get the same below threshold faults on Big Red but just ignore them as she goes through the MoT just fine. Could well be sensors if one is now dead. They are cheap enough, although I can't recall how heinous they are to change on the V6.

Hmm I have the car booked in for hand brake adjustment so might as well give them another job to do, especially that its wayyyyy cheaper than cats.. I'll report back once I have it back on the 11th

oooh someone's gonna hate you after those two :ROFL:

If the SAI valves are in the way like they are on the V8 its a 5-6 hour job.

I can attest that they are an absolute barsteward to get to, especially the post cat ones, and more especially the post cat on the nearside as the cable needs to be threaded over the bellhousing right over to the offside just behind the airbox. Only time I have ever been happy to have small hands ;)

The D2 design team are sadists......:(