P0420 and p0430
06-18-2013, 12:42 PM
#1
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P0420 and p0430
So after only getting the P0420 CEL, I replaced the upstream bank 1 O2 sensor. Not too bad, the only pita being putting new zip ties on the existing cables.
After approx 195 miles of driving i now get a p0420 and p0430 CEL. My car has 176k on the engine. I just got off the phone with a local exhaust shop and they asked which CATs am i referring to. I only assumed the car had 2, but apparently there's 4? Also he said that he is able to cut out the rear CATs and take a look to see what condition they're in. As well as check to see if one of the flex pipes are leaking which he said could trip those codes.
Totally at a lost guys I really cant afford dumping 3k for new OEM cats. I would most likely get the magnaflow or universal cats installed.
Thoughts??
After approx 195 miles of driving i now get a p0420 and p0430 CEL. My car has 176k on the engine. I just got off the phone with a local exhaust shop and they asked which CATs am i referring to. I only assumed the car had 2, but apparently there's 4? Also he said that he is able to cut out the rear CATs and take a look to see what condition they're in. As well as check to see if one of the flex pipes are leaking which he said could trip those codes.
Totally at a lost guys I really cant afford dumping 3k for new OEM cats. I would most likely get the magnaflow or universal cats installed.
Thoughts??
06-18-2013, 01:20 PM
#2
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At that mileage, it's guaranteed the issue will be the cats... They burn out.
Yes, you have 4 cats, 2 on each side. The first cat is measured by two O2 sensors - one pre-cat (sensor 1), one post-cat (sensor 2). Then you have a second cat, whose efficiency is not measured.
Replacing second cat(s) won't do squat for fixing your problem, and having a leak at the flex pipes is unlikely to affect the catalyst codes.
Your choice is to get a whole downpipe (and you need both banks), to the tune of $3K, or buy a cheap spark plug non-foulers (you need 2 of those), also known as O2 spacers. You install the spacers on the second O2 sensor, one per bank.
I've done the latter on my Allroad (which has only 95K miles).
Yes, you have 4 cats, 2 on each side. The first cat is measured by two O2 sensors - one pre-cat (sensor 1), one post-cat (sensor 2). Then you have a second cat, whose efficiency is not measured.
Replacing second cat(s) won't do squat for fixing your problem, and having a leak at the flex pipes is unlikely to affect the catalyst codes.
Your choice is to get a whole downpipe (and you need both banks), to the tune of $3K, or buy a cheap spark plug non-foulers (you need 2 of those), also known as O2 spacers. You install the spacers on the second O2 sensor, one per bank.
I've done the latter on my Allroad (which has only 95K miles).
06-18-2013, 04:13 PM
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Did you notice any performance gains with installing the sparkplug non foulers or did that just help eliminate the CEL for the p0420 and 0430 codes?
THanks!!
THanks!!
At that mileage, it's guaranteed the issue will be the cats... They burn out.
Yes, you have 4 cats, 2 on each side. The first cat is measured by two O2 sensors - one pre-cat (sensor 1), one post-cat (sensor 2). Then you have a second cat, whose efficiency is not measured.
Replacing second cat(s) won't do squat for fixing your problem, and having a leak at the flex pipes is unlikely to affect the catalyst codes.
Your choice is to get a whole downpipe (and you need both banks), to the tune of $3K, or buy a cheap spark plug non-foulers (you need 2 of those), also known as O2 spacers. You install the spacers on the second O2 sensor, one per bank.
I've done the latter on my Allroad (which has only 95K miles).
Yes, you have 4 cats, 2 on each side. The first cat is measured by two O2 sensors - one pre-cat (sensor 1), one post-cat (sensor 2). Then you have a second cat, whose efficiency is not measured.
Replacing second cat(s) won't do squat for fixing your problem, and having a leak at the flex pipes is unlikely to affect the catalyst codes.
Your choice is to get a whole downpipe (and you need both banks), to the tune of $3K, or buy a cheap spark plug non-foulers (you need 2 of those), also known as O2 spacers. You install the spacers on the second O2 sensor, one per bank.
I've done the latter on my Allroad (which has only 95K miles).
06-19-2013, 06:16 AM
#4
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Your car's performance will suffer if the first oxygen sensor fails, but the O2 spacers goes on the second sensor.
06-19-2013, 07:33 AM
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The 2nd set of sensors that are plugged into the secondary cats correct?
So the primary O2 was before the primary set of CAT's?
Well after I replaced the upstream sensor over the weekend, i did notice my mpg go back up. Also the car seems to have more pep. But being if the primary's are going bad I would imagine that its only going to get worse from a performance standpoint.
So the primary O2 was before the primary set of CAT's?
Well after I replaced the upstream sensor over the weekend, i did notice my mpg go back up. Also the car seems to have more pep. But being if the primary's are going bad I would imagine that its only going to get worse from a performance standpoint.
06-19-2013, 07:38 AM
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It appears that its possible to DIY remove and replace the downpipe assembly. Or i would try and find a local shop to do the work with customer provided parts.
06-19-2013, 08:03 AM
#7
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So after only getting the P0420 CEL, I replaced the upstream bank 1 O2 sensor. Not too bad, the only pita being putting new zip ties on the existing cables.
After approx 195 miles of driving i now get a p0420 and p0430 CEL. My car has 176k on the engine. I just got off the phone with a local exhaust shop and they asked which CATs am i referring to. I only assumed the car had 2, but apparently there's 4? Also he said that he is able to cut out the rear CATs and take a look to see what condition they're in. As well as check to see if one of the flex pipes are leaking which he said could trip those codes.
Totally at a lost guys I really cant afford dumping 3k for new OEM cats. I would most likely get the magnaflow or universal cats installed.
Thoughts??
After approx 195 miles of driving i now get a p0420 and p0430 CEL. My car has 176k on the engine. I just got off the phone with a local exhaust shop and they asked which CATs am i referring to. I only assumed the car had 2, but apparently there's 4? Also he said that he is able to cut out the rear CATs and take a look to see what condition they're in. As well as check to see if one of the flex pipes are leaking which he said could trip those codes.
Totally at a lost guys I really cant afford dumping 3k for new OEM cats. I would most likely get the magnaflow or universal cats installed.
Thoughts??
Point is that you can do OEM cats for roughly $2K and keep the car stock rather than mucked up.
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06-19-2013, 08:37 AM
#8
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Also keep in mind it is virtually impossible to get thse down pipes and cats out without a lift .. jack stands just arent going to get you high enough unless you are right up there .. they kind of go up and in with a half twist.
06-24-2013, 06:50 AM
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Thanks for the heads up.. I might be able to get access to a shop with a lift that I can use.
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