Cel on v8 lr3 with codes p0420 and p0116


Well-known member
Hoping for a plan to resolve check engine light on lr3 with codes of p0420 and p0116.

No issues with driving but light just came on. No exhaust odors or noises from exhaust. Around 150k on the odometer. I am original owner. I have not changed oxygen sensors or coolant sensors.
Where to do? Anyone with a smart plan ? K


NAS-ROW Addict
P0420 and your miles suggests to me that your cats are at the end of their Life cycle and need replacing. Often affecting drivability
P0401 is often associated with that code. That’s for the EGR valve.
P0116 is an engine temperature sensor.
Initially, at least, I’d check coolant level, reset the codes and see what codes return.


Well-known member
Thanks for the reply. I was hoping the expert response would be to replace oxygen sensors and all will be good.

I used my code reader to erase and therefore turn the light off.
There is plenty of coolant in the reservoir.

Now I will drive and see how long till cel comes back on.
Any thoughts and suggestions are welcome. Thanks in advance.
Is your battery still in good condition?
They usually throw off random codes when they are nearing replacement.
Sensors are easy to change and not too expensive too.

Sort these out and let us know.


Well-known member
Thanks for the replies. The battery is good. I don’t hear with my untrained ear any exhaust leak or rattle. The exhaust does not have any odor or black smoke.

The cel has not come back on. Is there a place for doing anything now ?