P0420 After Intake Install
Thread Starter
Intermediate
Joined: Nov 2022
Posts: 35
Likes: 36
From: Brevard, FL
P0420 After Intake Install
Good Afternoon,
So, a few months back, I installed 2MFabrication headers and sport cats. I've had no issues with the install other than it being a pain to do. A few thousand miles later I installed the Eventuri Intake. The next day I got a P0420 code for driver side o2. I thought it was maybe my connections. So I recheck all hose clamps on the intake, and my bolts/nuts on the headers/cats and all was tight. Reset code and about 20 miles later the code came back. Anyone have any ideas here? Thanks in advance for the help!
So, a few months back, I installed 2MFabrication headers and sport cats. I've had no issues with the install other than it being a pain to do. A few thousand miles later I installed the Eventuri Intake. The next day I got a P0420 code for driver side o2. I thought it was maybe my connections. So I recheck all hose clamps on the intake, and my bolts/nuts on the headers/cats and all was tight. Reset code and about 20 miles later the code came back. Anyone have any ideas here? Thanks in advance for the help!
Popular Reply
Nov 10, 2023, 04:09 PM
Race Director
Joined: Jan 2014
Posts: 10,709
Likes: 7,100
From: Fulshear, TX
Coincidental timing... Pretty typical experience after a few months with those low-quality generic cat cores. If you want to stick with the 2M cats, have you tried o2 sensor spacers? 2M sells some, but I'd personally recommend Big Daddies instead: http://www.bigdaddiesgarage.com/
If you're looking to build a reliable street or track machine though, I'd really suggest going with a higher quality cat core from either HJS or GESi.
If you're looking to build a reliable street or track machine though, I'd really suggest going with a higher quality cat core from either HJS or GESi.
Thread Starter
Intermediate
Joined: Nov 2022
Posts: 35
Likes: 36
From: Brevard, FL
I have a bit older of a code reader, Actron AutoScanner Pro (CP9190) I can't run an O2 test but it does give me volt readouts for S12 and S22, and an Amperage reading for S22. I did record 12 frames of data for that if that info would help?
I also do not believe I created any. I checked my hose clamps post MAF and everything is tight. So I don't think anything would be wrong there. If it was that, wouldn't I also get codes for both banks?
Thanks for the help!
Thread Starter
Intermediate
Joined: Nov 2022
Posts: 35
Likes: 36
From: Brevard, FL
I am working on a build to eventually track it pretty heavily, I am just making sure nothing has gone wrong to this point before I move forward. So I definitely want to not re-install the stock cats.
Race Director
Joined: Jan 2014
Posts: 10,709
Likes: 7,100
From: Fulshear, TX
Coincidental timing... Pretty typical experience after a few months with those low-quality generic cat cores. If you want to stick with the 2M cats, have you tried o2 sensor spacers? 2M sells some, but I'd personally recommend Big Daddies instead: http://www.bigdaddiesgarage.com/
If you're looking to build a reliable street or track machine though, I'd really suggest going with a higher quality cat core from either HJS or GESi.
If you're looking to build a reliable street or track machine though, I'd really suggest going with a higher quality cat core from either HJS or GESi.
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Thread Starter
Intermediate
Joined: Nov 2022
Posts: 35
Likes: 36
From: Brevard, FL
Coincidental timing... Pretty typical experience after a few months with those low-quality generic cat cores. If you want to stick with the 2M cats, have you tried o2 sensor spacers? 2M sells some, but I'd personally recommend Big Daddies instead: http://www.bigdaddiesgarage.com/
If you're looking to build a reliable street or track machine though, I'd really suggest going with a higher quality cat core from either HJS or GESi.
If you're looking to build a reliable street or track machine though, I'd really suggest going with a higher quality cat core from either HJS or GESi.
What’s Next
Joined: Dec 2020
Posts: 1,293
Likes: 834
From: Reality
+1 on Big Daddies. I have sport cats with the Gensi cores and they still ended up throwing a code after a few months and at the track. I'll delete the code for the secondary O2's when I get my tune pending what the tuner has to say about it. I've done this on other cars.
Catless is LOUD on this car.
Catless is LOUD on this car.
Intermediate
Joined: Nov 2023
Posts: 29
Likes: 24
Are you using the supplied 2m gaskets? Those seem to have a high failure rate. Im installjng mine here (headers, catless pipes, exhaust) in the next few weeks and went with oem gaskets, and bigdaddies o2 spacers and mini cat spacers. They seem to have a better outcome than 2m’s mini cat o2 spacers. Heres the links for both
http://www.bigdaddiesgarage.com/angled-cel-fix.html
http://www.bigdaddiesgarage.com/mini-cat-cel-fix.html
http://www.bigdaddiesgarage.com/angled-cel-fix.html
http://www.bigdaddiesgarage.com/mini-cat-cel-fix.html
Thread Starter
Intermediate
Joined: Nov 2022
Posts: 35
Likes: 36
From: Brevard, FL
So I think my path first is checking for a leak on the driver side, this is not the first I have heard about bad gaskets from 2m. I get using OEM gaskets from block to header but are their gaskets from the header to cat still okay to use, and if not is there a good alternative since I think OEM will not fit there.
If that does not show a leak, I plan to get improved spacers and mini cats from BDG. Thanks everyone for the help!
If that does not show a leak, I plan to get improved spacers and mini cats from BDG. Thanks everyone for the help!
Burning Brakes
Joined: Feb 2011
Posts: 833
Likes: 469
From: Goodyear AZ
So I think my path first is checking for a leak on the driver side, this is not the first I have heard about bad gaskets from 2m. I get using OEM gaskets from block to header but are their gaskets from the header to cat still okay to use, and if not is there a good alternative since I think OEM will not fit there.
If that does not show a leak, I plan to get improved spacers and mini cats from BDG. Thanks everyone for the help!
If that does not show a leak, I plan to get improved spacers and mini cats from BDG. Thanks everyone for the help!
I bet the 02 extensions would solve your problem. I've been running 2m cats for almost 3 yrs with no issue and have the 02 extensions on.
Thread Starter
Intermediate
Joined: Nov 2022
Posts: 35
Likes: 36
From: Brevard, FL
Bad Gasket
Thanks to everyone who commented ideas. I did do an exhaust leak test and there were several leaks on the garbage gasket that 2M provided. As some mentioned as well, I did have a slight ticking noise, but was told in the past it was injector noise and no worries. I went and got an OEM gasket from my local dealer (They had a ton in stock so I got a second for when the passenger side inevitably leaks). Swapped the gaskets and reset the code. Engine sound considerably better (tick is practically un-noticeable, the switch from v8 to v4 is smoother, and the CEL hasn't come back after 150 miles.
So fix is good, and thanks again for the community help!
So fix is good, and thanks again for the community help!
