dreaded PO420 - Camaro5 Chevy Camaro Forum / Camaro ZL1, SS and V6 Forums

stateroadhog · 09-05-2018, 04:33 PM

Installed set of solo hi flow cats. CEL pops every so often. Do have small leak on each flange. Is the leak at flange causing the Light? If so can I install two gaskets to help with seal? I have the rear extensions on the sensors.

JerTM · 09-05-2018, 06:33 PM

I'd seal it up, but I'm certain it's your cats. They aren't as efficient at cleaning up the exhaust as a factory cat.

zz430camaro · 09-05-2018, 07:32 PM

This code is from the hi-flow cats for sure, it will always come up. Take it to someone that can tune the car and turn off the reporting of his code.

09-05-2018, 04:33 PM	#1
stateroadhog Drives: 2015 SS/RS 1LE Join Date: Jun 2018 Location: Owosso, MI. Posts: 22	dreaded PO420 Installed set of solo hi flow cats. CEL pops every so often. Do have small leak on each flange. Is the leak at flange causing the Light? If so can I install two gaskets to help with seal? I have the rear extensions on the sensors.

09-05-2018, 06:33 PM	#2
JerTM Drives: 2011 2SS/RS M6 Join Date: Oct 2015 Location: Utah Posts: 1,940	I'd seal it up, but I'm certain it's your cats. They aren't as efficient at cleaning up the exhaust as a factory cat.

09-05-2018, 07:32 PM	#3
zz430camaro Drives: 2015 1LE Join Date: Oct 2015 Location: Cleveland, OH Posts: 1,498	This code is from the hi-flow cats for sure, it will always come up. Take it to someone that can tune the car and turn off the reporting of his code.