Best fix for check engine code PO4030
Drifting
Joined: Sep 2009
Posts: 1,719
Likes: 4
From: cinnaminson n.j.
St. Jude Donor '14
With an OBD2 vehicle the downstream o2's are there to monitor the catalyst operation. Read post 14. That info is straight from chevy diagnostics for p0430.
Drifting
Joined: Sep 2009
Posts: 1,719
Likes: 4
From: cinnaminson n.j.
St. Jude Donor '14
Some swear by this product, I haven't used it myself. We use a motorvac product.
http://www.cataclean.com
The sea foam should have helped. I had a rep from bosal exhaust at my shop who told me to do a fuel injection service to any car before installing a new cat. He was very convincing. The idea is to remove as much carbon from the engine so as to not have it coat the substrate in the new cat. We have been doing this for a couple years now when we use aftermarket cats and have not had the cars returning with the p0420-430 codes.
http://www.cataclean.com
The sea foam should have helped. I had a rep from bosal exhaust at my shop who told me to do a fuel injection service to any car before installing a new cat. He was very convincing. The idea is to remove as much carbon from the engine so as to not have it coat the substrate in the new cat. We have been doing this for a couple years now when we use aftermarket cats and have not had the cars returning with the p0420-430 codes.
Race Director
Joined: Apr 2007
Posts: 11,150
Likes: 890
From: South Western Ontario
I'm still not sure how replacing the post cat O2 sensors made the car run so much better. You can completely remove them without any effect on how the engine runs. You can tune them out by simply turning off the diagnostic codes related to them and then you don't get any codes.
Racer
Joined: Jun 2013
Posts: 256
Likes: 3
From: West Texas
I understand how it works. My point is that no one, including a dealer, is going to replace a cat without first testing it. It takes 30 seconds and will give you a definitive answer on whether or not the cat is bad.
Thread Starter
Racer
Joined: Mar 2005
Posts: 286
Likes: 36
From: Scituate, MA
The MIL came back, shopping for cats....
So after 157 miles, 6 days, and probably 20 key turns, the CE light kicked on again, and it is the dreaded PO430 again.
After resetting, it only went 38 miles, and 3 key turns, before another MIL. Am I endangering the new O2 sensors with a failing cat?
After that many miles, time, and starts, I thought I had it fixed. I guess OBD II is accurate, and I should heed its readings. I only hope that the reason that the cat or cats failed was age and or old failing o2 sensors, otherwise I may replace the cat assembly at great cost, and then have it fail again. That would not be good.
My focus is the Magnaflo 51397, which is newer than the 31998, and looks to have smaller cats, and it's slightly more $.
Has anybody tried this one, and did you pass emissions OK?
Best,
Bluemill
After resetting, it only went 38 miles, and 3 key turns, before another MIL. Am I endangering the new O2 sensors with a failing cat?
After that many miles, time, and starts, I thought I had it fixed. I guess OBD II is accurate, and I should heed its readings. I only hope that the reason that the cat or cats failed was age and or old failing o2 sensors, otherwise I may replace the cat assembly at great cost, and then have it fail again. That would not be good.
My focus is the Magnaflo 51397, which is newer than the 31998, and looks to have smaller cats, and it's slightly more $.
Has anybody tried this one, and did you pass emissions OK?
Best,
Bluemill
Thread Starter
Racer
Joined: Mar 2005
Posts: 286
Likes: 36
From: Scituate, MA
The check engine light came back, shopping for Cats...
So after 157 miles, 6 days, and probably 20 key turns, the CE light kicked on again, and it is the dreaded PO430 again. I had replaced both sets of O2 sensors with NTK's, and put in 12.8 gallons of fresh 93 octane, and did a high temp cat cook, all to no avail.
After resetting, it only went 38 miles, and 3 key turns, before another MIL. Am I endangering the new O2 sensors with a failing cat?
After that many miles, time, and starts, I thought I had it fixed. I guess OBD II is accurate, and I should heed its readings. I only hope that the reason that the cat or cats failed was age and or old failing o2 sensors, otherwise I may replace the cat assembly at great cost, and then have it fail again. That would not be good.
My focus is the Magnaflo 51397, which is newer than the 31998, and looks to have smaller cats, and it's slightly more $.
Has anybody tried this one, and did you pass emissions OK?
Best,
Bluemill
After resetting, it only went 38 miles, and 3 key turns, before another MIL. Am I endangering the new O2 sensors with a failing cat?
After that many miles, time, and starts, I thought I had it fixed. I guess OBD II is accurate, and I should heed its readings. I only hope that the reason that the cat or cats failed was age and or old failing o2 sensors, otherwise I may replace the cat assembly at great cost, and then have it fail again. That would not be good.
My focus is the Magnaflo 51397, which is newer than the 31998, and looks to have smaller cats, and it's slightly more $.
Has anybody tried this one, and did you pass emissions OK?
Best,
Bluemill
Thread Starter
Racer
Joined: Mar 2005
Posts: 286
Likes: 36
From: Scituate, MA
Ordered the Flowmaster 2010014....
Hope this works. Flowmaster is a reputable brand, and I may get a little more exhaust rumble out of it, plus more flow hp, and fuel economy. The warranty for emissions is 25,000 miles, and rust through of the casing 5 years. Not bad. The pipes go all the way back to the mufflers, instead of a chopped off rear to allow for X pipes. Also it's stainless.
Best always,
Bluemill
Best always,
Bluemill
Drifting
Joined: Sep 2009
Posts: 1,719
Likes: 4
From: cinnaminson n.j.
St. Jude Donor '14
Please read post 14 and explain to me what "a good exhaust shop" is going to do in 30 minutes or 30 seconds to "know for sure if you have a bad cat"?
The only quick test on an obd2 car would be to graph b2s1 and b2s2. The only way the cat monitor will even run is if everything else is working correctly.
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Thread Starter
Racer
Joined: Mar 2005
Posts: 286
Likes: 36
From: Scituate, MA
The Catalytic Cataclysm Part 29.....NOT GOOD
I got a Flowmaster model 2010014 cat-mid pipe assembly from Amazon yesterday, and tried to have it installed today at a Lou's Custom Exhaust, a 27 location New England franchise. They were super nice, and made a valiant attempt to get the pipes to fit, but it didn't fit 4 different ways, and that's not even trying to connect it to the rear mufflers.
The manager was kind enough to show me how "off" the new connections were, and they were not even close.
Now I have to send them back, and try something else.
Magnaflow? Any body try their cat/mid pipes set up, specifically model 51397?
Can you really test a cat's function somehow- or not, other than read the code off your DIC?
At the end of Sept. my safety/emissions annual sticker will expire, so I may need to park it for a while.
If anybody would sell me their used original mid cat pipes that would be good too!
Best,
Bluemill
The manager was kind enough to show me how "off" the new connections were, and they were not even close.
Now I have to send them back, and try something else.
Magnaflow? Any body try their cat/mid pipes set up, specifically model 51397?
Can you really test a cat's function somehow- or not, other than read the code off your DIC?
At the end of Sept. my safety/emissions annual sticker will expire, so I may need to park it for a while.
If anybody would sell me their used original mid cat pipes that would be good too!
Best,
Bluemill
Drifting
Joined: Sep 2009
Posts: 1,719
Likes: 4
From: cinnaminson n.j.
St. Jude Donor '14
Get a low mileage factory h pipe. It won't cost as much and will keep the light off. Think about it. The federal govt. makes the car companies warranty the original cats for 8 years or 80,000 miles. The aftermarket cats aren't required to have the 8/80 warranty.
Graphing the o2's with a good scanner is the best way to see if the cat will pass the diagnostic test the obd2 system runs every drive cycle.
Graphing the o2's with a good scanner is the best way to see if the cat will pass the diagnostic test the obd2 system runs every drive cycle.
Burning Brakes
Joined: Jan 2011
Posts: 1,067
Likes: 46
From: Springfield IL.
Oldtimer
What year is your car? All C5s are not the same. Does your car have the pup cats in front of the regular cats? The early C5s didn't have pup cats on them. My 99 only has 2 cats on it not 4.