P0430 CEL Code
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Driver School Candidate
Joined: Apr 2017
Posts: 29
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From: Virginia
P0430 CEL Code
Did some research for the P0430 CEL code. I purchased a spark plug non-fouler to hopefully trick the computer, but after a couple days the CEL came back on.
Instead of replacing the catalytic converter, are there any other fixes for this CEL code?
Instead of replacing the catalytic converter, are there any other fixes for this CEL code?
Lead Lap
Joined: Jun 2013
Posts: 527
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From: MA
You put the anti fouler on the rear o2 sensor correct? Also, did you verify that when the cel came back on, it is still for the same code?
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Driver School Candidate
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From: Virginia
Lead Lap
Joined: Jun 2013
Posts: 527
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From: MA
Yes, the O2 sensor (DENSO 2344509) to the rear of the cat. After installing the non fouler I cleared the code with a scanner and the same code came back a day or so later.
Thread Starter
Driver School Candidate
Joined: Apr 2017
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From: Virginia
I actually did buy a new sensor ($70) and did stack the non foulers until I had no space (about 2 of them). I don’t notice any abnormal smells.
Lead Lap
Joined: Jun 2013
Posts: 527
Likes: 56
From: MA
I'm not really sure then. I've heard replacing the precat o2 sensor can also affect it. I would give it a week or two and see if the CEL clears itself. I know in many cases the p0420/p0430 code is intermittent, so maybe with your solution it will be the same. Are you due for reinspection and need a clear dash to pass?
Thread Starter
Driver School Candidate
Joined: Apr 2017
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From: Virginia
I'm not really sure then. I've heard replacing the precat o2 sensor can also affect it. I would give it a week or two and see if the CEL clears itself. I know in many cases the p0420/p0430 code is intermittent, so maybe with your solution it will be the same. Are you due for reinspection and need a clear dash to pass?
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From: Virginia
Inspection is coming up and the check engine light and VSC light still are on. Occasionally the lights will turn off, but come back a day or so later. I ran my scan tool and its still showing the P0430 code with 2 descriptions:
- Catalyst System efficiency below threshold bank 2
- Circuit low voltage bank 1 sensor 2
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Joined: Aug 2002
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From: Colorado, USA
Most will likely say this is snake oil, but recently when our RX had the P0420 (CEL and VSC - catalyst system below threshold), I ran back-to-back bottles of Cataclean along with Shell premium. I cleared the codes and the P0420 has never come back. $25 down the drain if it doesn't work.
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Joined: Jul 2015
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From: pa
Most will likely say this is snake oil, but recently when our RX had the P0420 (CEL and VSC - catalyst system below threshold), I ran back-to-back bottles of Cataclean along with Shell premium. I cleared the codes and the P0420 has never come back. $25 down the drain if it doesn't work.
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Joined: Aug 2002
Posts: 620
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From: Colorado, USA
It has not.
The shop that diagnosed a bad cat wanted $1300 to replace it and they wouldn't clear the code. I couldn't get a clear answer if they were simply going off the MIL code or if they did additional diagnosis. I picked up the car with the light still on and ran cataclean through (two bottles), manually cleared the code myself and it hasn't come back. That was ~4,000 miles ago (getting ready to turn 257,000 miles).I have read mixed reviews on the product, but it worked for my situation.
edit: I forgot to mention, I also passed the bi-annual emissions test (fast-track) for Colorado after running the bottles through.
The shop that diagnosed a bad cat wanted $1300 to replace it and they wouldn't clear the code. I couldn't get a clear answer if they were simply going off the MIL code or if they did additional diagnosis. I picked up the car with the light still on and ran cataclean through (two bottles), manually cleared the code myself and it hasn't come back. That was ~4,000 miles ago (getting ready to turn 257,000 miles).I have read mixed reviews on the product, but it worked for my situation.
edit: I forgot to mention, I also passed the bi-annual emissions test (fast-track) for Colorado after running the bottles through.
Last edited by cdnewton; Jun 27, 2020 at 10:47 AM. Reason: added emissions testing
Driver School Candidate
Joined: Jul 2015
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From: pa
It has not.
The shop that diagnosed a bad cat wanted $1300 to replace it and they wouldn't clear the code. I couldn't get a clear answer if they were simply going off the MIL code or if they did additional diagnosis. I picked up the car with the light still on and ran cataclean through (two bottles), manually cleared the code myself and it hasn't come back. That was ~4,000 miles ago (getting ready to turn 257,000 miles).I have read mixed reviews on the product, but it worked for my situation.
edit: I forgot to mention, I also passed the bi-annual emissions test (fast-track) for Colorado after running the bottles through.
The shop that diagnosed a bad cat wanted $1300 to replace it and they wouldn't clear the code. I couldn't get a clear answer if they were simply going off the MIL code or if they did additional diagnosis. I picked up the car with the light still on and ran cataclean through (two bottles), manually cleared the code myself and it hasn't come back. That was ~4,000 miles ago (getting ready to turn 257,000 miles).I have read mixed reviews on the product, but it worked for my situation.
edit: I forgot to mention, I also passed the bi-annual emissions test (fast-track) for Colorado after running the bottles through.
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Joined: Aug 2002
Posts: 620
Likes: 101
From: Colorado, USA
https://www.walmart.com/ip/Cataclean...6-oz/135378546
Driver School Candidate
Joined: Jul 2015
Posts: 12
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From: pa
I used the one at the link below ... I picked it up at Advance Auto parts for $24.95, but now WalMart carries it for less. I also ran a couple of tanks of Shell premium through before the emissions test. Why? Most likely a sucker for advertising, but figured it couldn't hurt. The combo worked in my situation (both MIL and emissions testing), but there were definitely mixed reviews on Cataclean.
https://www.walmart.com/ip/Cataclean...6-oz/135378546
https://www.walmart.com/ip/Cataclean...6-oz/135378546