Hello

I am the owner of a Lexus Rx 450h F-sport and I want to ask for some advice
with a problem I am encountering. About a month ago, my wife filled up
with diesel instead of petrol and drove a few km until he realized and then he pulled
car on the right. The car was towed to a service center that removed the entire pump
diesel from the tank. I filled up with gasoline and drove it at higher revs to clean it
injectors on the advice of the service mechanic. Even if I left the service without any
an error after about 100 km, the Check Engine on board came on and on OBD it gives me the error P0420
which tells me "Catalyst System Efficient Below Threshold". I want to specify that the car is running
perfect and every time I delete this error at about 140 Km it reappears.
Now I have 2 options:
Variant 1 proposed by the Lexus representative: I go a few hundred km more and if it reappears
I should change the catalyst at them (the Lexus representative does not clean the catalyst)

Option 2: I take off the catalyst and take it for cleaning, but that means cutting the 4m pipe
length to be able to enter the cleaning room and then mounted back with a kit
mounting.

I mention that the car is from 2019 and has 120,000 km and I want to know if anyone else has experienced this
something like that and if there is a solution or a suggestion, I honestly don't really want to cut the pipe
from the catalyst and I wouldn't put a new one if the car doesn't have any problems.