Possible Solution for Catalytic Converter fault codes - P0421 & P0431
04-07-2011, 03:47 PM
#22
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or alternatively you can run ~ 2 cups of acetone per each 20g in the fuel tank and it should have a "cleaning" effect on your O2 sensors. (I wouldn't do it) i will just put in a new cat and be done with it. 6 bolts to wrestle,l 2 O2 sensors R&R and in it goes. Going with the flea-bay lifetime warranty direct fit replacement..... any one used them before????
oh and before anyone starts trying to "educate" me on the "you get what you pay for" subject. There are only 2-3 washcoat suppliers in the world, and all have comparable quality control. I should know this as i used to design catalytic converters for an oem in the past.
oh and before anyone starts trying to "educate" me on the "you get what you pay for" subject. There are only 2-3 washcoat suppliers in the world, and all have comparable quality control. I should know this as i used to design catalytic converters for an oem in the past.
04-18-2011, 03:11 AM
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I didn't had to replace my cat. On my a6 3.0 88.000 miles. All I did was switch gas to premium. Now I only use shell v power.
08-22-2012, 07:56 AM
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08-23-2012, 10:47 PM
#27
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The light never came back but I sold the car shortly after I installed the spacers. As for the BG 44K I ran two cans. I filled my tank, added the 44K, ran the tank dry, and did it again. After that I was told to add one can every ten fill ups. I've left the woeful and expensive world of Audi and am now comfortable settled in the Lexus club with no regrets.
10-31-2012, 04:36 PM
#28
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There are 2 certain cures. The first is to run ethanol free high test. I dd this on a road trip for ver 1500 miles till I got back to Florida where we add ethanol, light back on in 50 miles.
The other is to install a K & N air filter. Light gone and stays gone 4 months now.
My explanation, ethanol burns with more carbon residue partly due to absorbed moisture, this carbon forms a thin coating on the cat screens reducing heating efficiency. Freer flowing air intake, slightly reduce sunburnt residue.
I know it works though. If you can get ethanol free gas, USE IT! There are other issues associated with ethanol in gasoline engines that make it totally unacceptable if you intend to keep your car beyond the warranty period.
The other is to install a K & N air filter. Light gone and stays gone 4 months now.
My explanation, ethanol burns with more carbon residue partly due to absorbed moisture, this carbon forms a thin coating on the cat screens reducing heating efficiency. Freer flowing air intake, slightly reduce sunburnt residue.
I know it works though. If you can get ethanol free gas, USE IT! There are other issues associated with ethanol in gasoline engines that make it totally unacceptable if you intend to keep your car beyond the warranty period.
09-14-2013, 01:58 AM
#29
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P0421 or P0431 fault fix
10-13-2016, 02:07 PM
#30
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Use Vibrant 16119
I used this for my 2005 Audi TT 3.2 DSG. I installed Magnaflow OEM replacement cats and could not get it to reset the ECM. I installed the restrictors and used the "small" restrictor as first recommended by the manufacturer (if they provided instructions it would be helpful) and after driving the car for 25 miles...all values were reset. The "C" clips are tight and I highly recommend having a tool (which I had) to install them. I tried without them and could not get to reset after 200 miles. The Audi dealer could not get to reset either. After we called private shops I was told of these restrictors and they do just what they say! Very pleased
