P0420 fault code. Catalytic system
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P0420 fault code. Catalytic system
Hi
I had the yellow engine “environmental” warning light come on, so plugged in an OBD reader I borrowed.
Gave the code P0420. Catalytic system efficiency below threshold (Bank 1).
It had the cat replaced and an after market exhaust fitted previously.
Do you think I’m OK to drive it (seems fine)? Any suggestions to fix?
I had the yellow engine “environmental” warning light come on, so plugged in an OBD reader I borrowed.
Gave the code P0420. Catalytic system efficiency below threshold (Bank 1).
It had the cat replaced and an after market exhaust fitted previously.
Do you think I’m OK to drive it (seems fine)? Any suggestions to fix?
Joined: Jun 2007
Posts: 326
Likes: 9
I got the same warning when I had an aftermarket CAT fitted on my car many years ago. I still drove it for years racking up the mileage and it did not cause a problem so the car will be fine to drive.
I believe it was because of the O2 sensor and I think the recommended solution was to add a spacer to the O2 sensor but I never bothered. I would just reset the warning whenever it needed to be MOT'd. I now have a Berk cat fitted which already has the spacer and the warning light no longer appears.
I believe it was because of the O2 sensor and I think the recommended solution was to add a spacer to the O2 sensor but I never bothered. I would just reset the warning whenever it needed to be MOT'd. I now have a Berk cat fitted which already has the spacer and the warning light no longer appears.
Joined: Mar 2004
Posts: 23,298
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From: Nottingham
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