View Full Version : Engine Light Problems After Replacing Cat


GXP303
06-18-2010, 10:05 PM
Hello. New to the board. I own a 2008 Grand Prix GXP. I just replaced my exhaust system with a magnaflow catback system. I also replaced the cat with a high-flow cat. My engine light is turning on and I can no longer use my remote start feature. Should I put the stock cat back on? I Know these next comments sound crazy but it happened so here goes nothing. The other day I was parked off to the side of the road while on a phone call and abruptly It sounded and felt like someone hit my car. It jolted like it was hit. Any clue? Any help would be much appreciated. Thanks.

monte_with_a_LS4
06-18-2010, 11:01 PM
Hello. New to the board. I own a 2008 Grand Prix GXP. I just replaced my exhaust system with a magnaflow catback system. I also replaced the cat with a high-flow cat. My engine light is turning on and I can no longer use my remote start feature. Should I put the stock cat back on? I Know these next comments sound crazy but it happened so here goes nothing. The other day I was parked off to the side of the road while on a phone call and abruptly It sounded and felt like someone hit my car. It jolted like it was hit. Any clue? Any help would be much appreciated. Thanks.

welcome! getting it tuned will take care of the CEL and was it the wind from cars passing you while u were sitting still maybe lol

smug_GXP
06-18-2010, 11:31 PM
I have the high flow cat with a 3 inch down pipe and I do not get a light because I have done the O2 sensor mod
http://www.energeticforum.com/renewable-energy/1387-o2-sensor-modification-using-spark-plug-non-foulers.html

williamGT
06-19-2010, 12:43 AM
Welcome:) you got a PM that i replied to you message.

Count of Monte Carlo
06-19-2010, 07:30 AM
The stainless steel O2 sensor extension does work. I havent had a light in 2.5 months. Nice to know I can stil use the down pipe.

StealthV8
06-19-2010, 01:50 PM
just get it tuned out. i ditched the cat and have had the light on for awhile now since i havn't been able to get to my tunner and my A/F ratio is still in check so i wouldn't worry.

GXP303
06-20-2010, 02:02 AM
Thank You for the replies and suggestions. Very Helpful.