header installation
Thread Starter
Staging Lane
Joined: Jul 2004
Posts: 85
Likes: 0
From: chicagoland
header installation 
throwing P0420 code, probabley a cat right?
instead of taking to GM
thought about a header installation!
hooker ceramic coated LT'S
ORY not sure if coated
AIR delete
rear 02 delete
a/f ratio adjustment, price for all is 1802.00
do not have time to do it myself this month, and have an emissions test in June
1802.00 WTF, less than a thousand in parts!
spend a couple hundred for single cat?
not going to a dealer.
just trying to find reality in 1802.00
TECH Veteran
Joined: Dec 2004
Posts: 4,012
Likes: 1
From: Beaumont, TX
Here's some information about possible causes of the P0420 code:
https://ls1tech.com/forums/pcm-diagnostics-tuning/41927-code-p0420-keeps-coming-up-what.html
http://www.v8sho.com/SHO/P0420APrimer.htm
http://www.alldata.com/techtips/2003/20031110a.html
This might be correctable by just getting the O2 checks turned off in the PCM. There are a number of people on this board in the Chicago area. You could try asking in the Midwestern forum if someone in the area who has the HP Tuners software would be willing to do that for a small fee
https://ls1tech.com/forums/pcm-diagnostics-tuning/41927-code-p0420-keeps-coming-up-what.html
http://www.v8sho.com/SHO/P0420APrimer.htm
http://www.alldata.com/techtips/2003/20031110a.html
This might be correctable by just getting the O2 checks turned off in the PCM. There are a number of people on this board in the Chicago area. You could try asking in the Midwestern forum if someone in the area who has the HP Tuners software would be willing to do that for a small fee
