CEL code P0420...SOLO exhaust related? - Camaro5 Chevy Camaro Forum / Camaro ZL1, SS and V6 Forums

Yellow Camaro · 11-04-2012, 01:09 PM

So I got a check engine light the other day, and was able to have the code read today P0420 Catalyst Efficiency low-bank 1.

The readout from Autozone lists probable causes as
-Catalytic converter defective
-engine misfire or running condition
-large vacuum leak
-engine oil leakage into exhaust-valve guide seals, piston rings.

I noticed a guy with a similar exhaust set-up was posting in here about a CEL, and the hyposthesis was that he needed stainless extenders instead of aluminum ones with his SOLO hi-flows. That's what I was thinking, except his code turned out to be P0137.

The only mods to the car are the Mach XL exhaust, SOLO hi-flows, and a CAI. Where should I start looking?

Also, a few people have mentioned around the forums that with the SOLO cats it makes sense to upgrade from aluminum to stainless extenders. I don't know much about these. Would all exhausts ordered from SOLO have shipped with aluminum? Are the correct stainless ones universal enough that they'd be available at an exhaust shop or auto parts store. I know SOLO would probably hook me up, but I'm concerned it's running too rich and I'll burn up a cat or something. HELP!!!

04GOAT-11SS · 11-04-2012, 01:19 PM

If you look around you'll see a lot of people are getting cat efficiency codes with high flow cats. Most just aren't made to the same standards as the OE cats and will throw a code. O2 extenders may work but to be sure you'll have to get the codes turned off with a tune. Otherwise it will set the code every couple hundred miles.

Yellow Camaro · 11-04-2012, 01:29 PM

I've had the system in place for 14 months and about 12,000 miles without issue. That's why it's confusing.

I did read a few threads about people "tuning it out". It seemed like most of those people had headers though. I've been debating a tune anyway....but feel like the car should be able pass inspection and run without issue without one- and has for a year plus.

I'm also really concerned (admittedly because I don't know what I'm talking about and the Autozone guy put rats in my head)....that running it like this is going to damage one of my cats.

IndeedSS1 · 11-04-2012, 03:42 PM

Quote:

Originally Posted by Yellow Camaro

I've had the system in place for 14 months and about 12,000 miles without issue. That's why it's confusing.

I did read a few threads about people "tuning it out". It seemed like most of those people had headers though. I've been debating a tune anyway....but feel like the car should be able pass inspection and run without issue without one- and has for a year plus.

I'm also really concerned (admittedly because I don't know what I'm talking about and the Autozone guy put rats in my head)....that running it like this is going to damage one of my cats.

If you have their extenders you should not be getting a code. Most likely one of the etenders have backed out. I have 30k on SOLO cats with no codes. My aluminum extenders kept backing out, but the stainless steel ones haven't.

At least verify there are no leaks and that the extenders and sensors are tight.

Cincy10SSRS · 11-05-2012, 07:42 AM

Quote:

Originally Posted by IndeedSS1

If you have their extenders you should not be getting a code. Most likely one of the etenders have backed out. I have 30k on SOLO cats with no codes. My aluminum extenders kept backing out, but the stainless steel ones haven't.

At least verify there are no leaks and that the extenders and sensors are tight.

There's a looong story attached to this but I won't bore you with it now. Here's the shorter version: My Solo hi-flow cats had the aluminum O2 extenders originally. They kept backing out, lately to the point where the O2 sensors weren't able to read properly and it was throwing a CEL.
Solo recognized well over a year ago that the aluminum extenders (they buy them from a sub-contractor) weren't the answer and switched to a much sturdier stainless steel version; they're alot different. At my request, Steve @ Solo sent me a pair free last week.
On my way to having them swapped out at a great small local exhaust shop the left extender actually FELL OUT of the cat bung hole, came detached from the sensor, and that (at the end of the lead wires) was bouncing along the road!
Of course it was ruined so I had to also stop at the Chevy dealership, buy a new sensor assy and then went to the exhaust shop. They put them in, cleared the code and all is well with the world.
The new extenders make for a much tigheter fit/connection and I think they will be fine for the long haul so get them if yours are aluminum. (Sorry, that was still kind of long!)

Yellow Camaro · 11-05-2012, 09:05 AM

Hey thanks, I think you were the guy I was referencing in my first post up top. I wasn't sure I was having the same issue because we got different codes...you got P0137, correct? I have P0420.

I purchased my exhaust direct from Steve @ SOLO in August of 2011. Is it a safe bet that I have the aluminum?

IndeedSS1 · 11-05-2012, 09:14 AM

Quote:

Originally Posted by Yellow Camaro

Hey thanks, I think you were the guy I was referencing in my first post up top. I wasn't sure I was having the same issue because we got different codes...you got P0137, correct? I have P0420.

I purchased my exhaust direct from Steve @ SOLO in August of 2011. Is it a safe bet that I have the aluminum?

I'm not sure when and for how long they tried out the aluminum ones. The code would make me think that you didn't have extenders in, but maybe that one back out. But I'd definitely check that first.

Cincy10SSRS · 11-05-2012, 09:17 AM

Quote:

Originally Posted by Yellow Camaro

Hey thanks, I think you were the guy I was referencing in my first post up top. I wasn't sure I was having the same issue because we got different codes...you got P0137, correct? I have P0420.

I purchased my exhaust direct from Steve @ SOLO in August of 2011. Is it a safe bet that I have the aluminum?

Hmm, I kind of had the impression they had made the switch to stainless by then. If you have a chance to get under your car without alot of trouble you could eyeball/touch the ones you have. The aluminum ones are slightly dull looking and kind of easily scratched; the stainless are shiny and harder.

Jason@JacFab · 11-05-2012, 09:47 AM

Yup, check the extenders, check for exhaust leaks, etc... Also, there is no need to worry about burning the cat up because of the code being thrown. The code basically means that the car thinks the cats are bad because it's not seeing what it thinks it should be seeing on the rear o2 sensor signal, which is typical of a high flow cat, as it's not burning up as much of the polutants in the exhaust gas as the factory restrictive cat.

tramtwo · 11-05-2012, 03:09 PM

This weekend I took off my headers and cats.... taking it back to stock. Anyway I forgot to remove the extenders and this car was acting like it is possessed. Had me scratching my head for a while. Especially when the code that was returned was P0380 (crazy) and the service stabilitrak message was flashing intermittently.

Cincy10SSRS · 11-05-2012, 03:16 PM

Quote:

Originally Posted by tramtwo

This weekend I took off my headers and cats.... taking it back to stock.

Trading it in?

tramtwo · 11-05-2012, 03:21 PM

Quote:

Originally Posted by Cincy10SSRS

Trading it in?

Sorta of... it is a GM buyback. Getting a 1LE soon.

Cincy10SSRS · 11-05-2012, 03:47 PM

Quote:

Originally Posted by tramtwo

Sorta of... it is a GM buyback. Getting a 1LE soon.

Nice, I guess, but I don't really get the whole 1LE thing. Isn't it just an SS with handling a little better for track/road course driving and if so who really does alot of that? Doesn't seem worth the upgrade $$.

tramtwo · 11-05-2012, 04:10 PM

Quote:

Originally Posted by Cincy10SSRS

Nice, I guess, but I don't really get the whole 1LE thing. Isn't it just an SS with handling a little better for track/road course driving and if so who really does alot of that? Doesn't seem worth the upgrade $$.

It is a bit more than JUST that. Just the wheels and tires are worth the upgrade money. I also was looking for a new hobby and there is a new track about a 15 minute ride from here.

11-04-2012, 01:09 PM	#1
Yellow Camaro Drives: 2010 Rally Yellow 2SS/RS Join Date: Jul 2011 Location: Boston, MA Posts: 417	CEL code P0420...SOLO exhaust related? So I got a check engine light the other day, and was able to have the code read today P0420 Catalyst Efficiency low-bank 1. The readout from Autozone lists probable causes as -Catalytic converter defective -engine misfire or running condition -large vacuum leak -engine oil leakage into exhaust-valve guide seals, piston rings. I noticed a guy with a similar exhaust set-up was posting in here about a CEL, and the hyposthesis was that he needed stainless extenders instead of aluminum ones with his SOLO hi-flows. That's what I was thinking, except his code turned out to be P0137. The only mods to the car are the Mach XL exhaust, SOLO hi-flows, and a CAI. Where should I start looking? Also, a few people have mentioned around the forums that with the SOLO cats it makes sense to upgrade from aluminum to stainless extenders. I don't know much about these. Would all exhausts ordered from SOLO have shipped with aluminum? Are the correct stainless ones universal enough that they'd be available at an exhaust shop or auto parts store. I know SOLO would probably hook me up, but I'm concerned it's running too rich and I'll burn up a cat or something. HELP!!!

11-04-2012, 01:19 PM	#2
04GOAT-11SS Drives: 2011 2SS/RS 2004 GTO Join Date: Sep 2012 Location: Long Island NY Posts: 42	If you look around you'll see a lot of people are getting cat efficiency codes with high flow cats. Most just aren't made to the same standards as the OE cats and will throw a code. O2 extenders may work but to be sure you'll have to get the codes turned off with a tune. Otherwise it will set the code every couple hundred miles.

11-04-2012, 01:29 PM	#3
Yellow Camaro Drives: 2010 Rally Yellow 2SS/RS Join Date: Jul 2011 Location: Boston, MA Posts: 417	I've had the system in place for 14 months and about 12,000 miles without issue. That's why it's confusing. I did read a few threads about people "tuning it out". It seemed like most of those people had headers though. I've been debating a tune anyway....but feel like the car should be able pass inspection and run without issue without one- and has for a year plus. I'm also really concerned (admittedly because I don't know what I'm talking about and the Autozone guy put rats in my head)....that running it like this is going to damage one of my cats.

11-05-2012, 09:05 AM	#6
Yellow Camaro Drives: 2010 Rally Yellow 2SS/RS Join Date: Jul 2011 Location: Boston, MA Posts: 417	Hey thanks, I think you were the guy I was referencing in my first post up top. I wasn't sure I was having the same issue because we got different codes...you got P0137, correct? I have P0420. I purchased my exhaust direct from Steve @ SOLO in August of 2011. Is it a safe bet that I have the aluminum?

11-05-2012, 09:47 AM	#9
Jason@JacFab Drives: 2016 1LT RS Camaro; 72 Chevelle Join Date: Apr 2008 Location: Central Point, OR Posts: 5,688 View My Garage	Yup, check the extenders, check for exhaust leaks, etc... Also, there is no need to worry about burning the cat up because of the code being thrown. The code basically means that the car thinks the cats are bad because it's not seeing what it thinks it should be seeing on the rear o2 sensor signal, which is typical of a high flow cat, as it's not burning up as much of the polutants in the exhaust gas as the factory restrictive cat.

11-05-2012, 03:09 PM	#10
tramtwo Drives: 2021 1LE Join Date: Jul 2011 Location: N'Awlinz Posts: 6,315	This weekend I took off my headers and cats.... taking it back to stock. Anyway I forgot to remove the extenders and this car was acting like it is possessed. Had me scratching my head for a while. Especially when the code that was returned was P0380 (crazy) and the service stabilitrak message was flashing intermittently.