Catalytic converters for a Gx470 (2 Viewers)
- Thread starter Bamagirl
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Sorry. I hope you made progress. I do the diagnostics online, buy the parts online, and then I pay an independent mechanic for the labor.
Yeah I replaced the o2 sensor on my 80 myself. It was easy. I looked at the Gx and looked more difficult, so I went to Indy mechanic.
I’ve replaced all my O2 sensors since this post haha
Her or her GX?
I think she had a run of $pendy repairs.
AIR, she got out of the GX and into a newer 4dr taco which provided a better camping setup.Not sure if she's still active in mud.
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To resurrect this thread; Has anyone has success clearing 'catalytic efficiency low' codes after replacing both downstream O2 sensors?
I'm currently facing 2 last choices (tried everything else), either replace the 2 downstream sensors or change out both exhaust manifolds with CATs.
I'm currently facing 2 last choices (tried everything else), either replace the 2 downstream sensors or change out both exhaust manifolds with CATs.
If you are getting a PO420, have you tried the spark plug antifouler mod? This has worked for many people on many different vehicles.
Anyone recommend O2 sensors that are decently priced? Also what antifoulers yall using.
GX DAVE
SILVER Star
Bought one of these back in march, no problems yet!
Also what antifoulers yall using.
Info here: Spark plug anti-fouler - https://www.mazda3forums.com/threads/spark-plug-anti-fouler.288174/
Info here: Spark plug anti-fouler - https://www.mazda3forums.com/threads/spark-plug-anti-fouler.288174/
Has anyone tried Oxicat (or something like it)? Seems like this stuff works some times and should be the first step but nobody here mentioned it. Anyone with any experience?
Also, many replace one O2 sensor but advice on the web says do both downstream ones at the same time. Advice?
Also, concerning the "antifoulers". I have never heard them called that but I had to use one on an engine swap once. It pulls the o2 sensor out of the main exhaust stream a bit and "lowers" the reading. It worked perfect for my car (2003 MR2). It is not trying to defeat the cat but to adjust it a bit. From what I read, on older cars this can help. I think only use it on the downstream one, though.
Also, many replace one O2 sensor but advice on the web says do both downstream ones at the same time. Advice?
Also, concerning the "antifoulers". I have never heard them called that but I had to use one on an engine swap once. It pulls the o2 sensor out of the main exhaust stream a bit and "lowers" the reading. It worked perfect for my car (2003 MR2). It is not trying to defeat the cat but to adjust it a bit. From what I read, on older cars this can help. I think only use it on the downstream one, though.
Replace O2 sensors in pairs….that what I did with denso ones.
I also cleaned the MAF sensor for kicks and giggles.
Cat cleaners are a hit and miss. I guess it’s worth a try but I never tired that. I went to a couple of places to inquire but neither thought it was going to fox my issue once the p0420 and p0430 showed up consistently and frequently within 50 miles or less.
Anti foulers are illegal in Cali and i didn’t want to go that route. I ended up replacing the integrated cats and solved all my cat
Problems.
I had the same issues with P0420/0430. These codes are most definitely catalytic converters. Each 02 sensor has its own sets of codes. I replaced all 4 02 sensors anyways, didn't have any affect on the codes. I purchased two of these for the rear 02 sensors- O2 Simulator Mini Cat Cel Fix stainless steel Rear O2 sensor simulator. - http://www.bigdaddiesgarage.com/mini-cat-cel-fix.html. They are basically a mini-cat for the rear 02 sensors. Codes have been cleared and haven't come back and I passed the ECU check for GA emissions. We also have a visual inspection, but in my experience, no one has every looked at anything other than plugging in the ECU and checking the gas cap. I've got DT LT headers on hand and plan to replace the factory manifolds/cats with LT headers. I've only found one shop to take on the job and they quoted me 8hrs @190/hr. I've found a friend/shadetree mechanic to do it for half that.
Lost my login info when I cleared my browser history and didn't set up 2FA. Anyways, the mini cats worked for about a few weeks, enough for me to pass emissions, but 420/430 came back.
I found this: Toyota-4Runner.org - https://www.toyota-4runner.org/3rd-gen-t4rs/175242-how-make-your-own-rear-o2-simulator-%245.html but it seems the 1M/1uf aren't working, so next up will be a 1000uf/4.7kohm resistor to get a longer time constant.
Also found this, which was recommending an additional resistor: RC Low-pass filter for O2 sensor - https://forum.allaboutcircuits.com/threads/rc-low-pass-filter-for-o2-sensor.166214/
