Our 2013 Volvo S80 recently threw a P0420 code. Clearing it, did turn off the CEL but the code remained as "Permanent" on my code reader. The car only has 76k miles, so I wasn't convinced it was actually the CATs. Anyway, I thought I'd try a bottle of Cataclean. I poured it in at ~1/4 tank as instructed, but I drove it a little longer than they say before filling up. They say drive 10-15 minutes. I drove 30 miles at 65MPH, before refilling. I didn't track when the code disappeared with any regularity, but I did check roughly two weeks later and the code was no longer showing on my code reader. I was impressed enough that I used a bottle on my 2003 Civic with 180k (which has original CATs and has never thrown a P0420) as a preemptive measure. Why not?
Cataclean "erased" permanent P0420 code
- Thread starter himemsys
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- Jul 10, 2022
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It’s difficult to determine the cause and effect imho…in our car we got that code Xmas 2020 and it never came back for almost 2 years. We didn’t do anything and at the time I hadn’t realized the stored and pending codes. The car has to clear them on our 2011 GM. Battery disconnect doesn’t do it
I agree and intentionally worded my post to try not to imply that. But if it did, then it was easily worth the $22 the bottle cost. I bought a two-pack, ($44 on Amazon) so it was a no-brainer to use the 2nd bottle in my Civic.
it will come back....
EDIT: Wrong Thread!
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Naturally aspirated 3.2l. No oil consumption since we bought it at 63k. Hoping it stays that way!
Well it ain't oil causing that cat to be damaged. Hopefully it stays that way since the cat won't handle any more.
Maybe you meant to post in a different thread?
Yea, pass it along to the next unsuspecting doofus. Human nature is interesting. We never think that OUR time is next…until it’s next…then we rage.
+1 My thought also. O2 sensors age out with use. If the readings the ecu sees are outside normal range long enough, it could be that the readings they send are not quick enough and accurate enough to allow the ecu to properly adjust the engine air/fuel rario and spark to make a good cat show as a good cat. Also, clean maf and map as those are also vital inputs to the ecu.
Of course it could be a bad cat. But it could also be one or more bad sensors. Any O2 sensor with > 60k miles could be going bad. Remember GIGO (garbage in garbage out). Computers that control things can't do their jobs if the information fed to them is garbage.
o2 sensor could be an option but often times these codes are from the cat itself. Cleaners and o2 sensor did not help this code in my '03 Corolla. However, a spark plug non-fouler did the trick!
To add to this with my anecdotal evidence, I started getting a P0420 in my Subaru STI with around 70K miles, I tried clearing it and using other fuel adds without succcess over 5k miles. It's older than 10 years so no warranty left. I was starting to get power loss and hesitation as well.
I suspect it was from numerous track day sessions over it's life, the stock ECU tune make these cars super rich on WOT. They absolutely dump fuel to cool the turbo/EGT at around 10 AFR, the stock wideband only goes to 11 and was capping it out.
I tried everything other than replacing parts, a new cat isn't cheap and landed on cataclean snake oil .
No more P0420
for 10k miles so far.
I suspect it was from numerous track day sessions over it's life, the stock ECU tune make these cars super rich on WOT. They absolutely dump fuel to cool the turbo/EGT at around 10 AFR, the stock wideband only goes to 11 and was capping it out.
I tried everything other than replacing parts, a new cat isn't cheap and landed on cataclean snake oil .
No more P0420
for 10k miles so far.
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I have a 2006 elantra with 198K miles and my daughter just get a forster with 116K miles .. both run what appers to be fine and not CEL or showing.. was wondering if worthwhile to run a bottle of this through gas to help head off any issues with cat in the future or wait till i get at light on.??
I do run a bottle or two of chevron techron through the tank every time i get a chance to which can be 10-12 months apart..
I do run a bottle or two of chevron techron through the tank every time i get a chance to which can be 10-12 months apart..
I did as much with my Civic, as I mentioned in my opening post. I can't see it hurting, and it could possibly do as you say, be a preventative measure against cat/o2 issues.
Wish that worked for my 2015xc70 T6, 3l turbo. Did 2 Cataclean runs and tried STPs version of cat clean. No joy as of yet.
However, downstream 02 would always fluctuates erratically before CataClean, now at idle it is relatively stable. Driving is a different story as it continues to fluctuate and code comes on every day or 3.
Downstream 02 will be replaced in the coming weeks for good measure. 140k miles.
However, downstream 02 would always fluctuates erratically before CataClean, now at idle it is relatively stable. Driving is a different story as it continues to fluctuate and code comes on every day or 3.
Downstream 02 will be replaced in the coming weeks for good measure. 140k miles.
