Windjunkie
02-14-2008, 02:07 PM
I've searched but couldn't find this topic here or GAGT.com, any help appreciated.
Simple question: Is there a difference in CAT effeciency required to pass emissions test (ie, and not throw a P0420 code) between California cars and others?
Background: 2002 GA GT : 6 months ago my ignition wires were shorting causing unburned fuel to enter the exhaust. it fried and plugged my CAT so I got a new "universal" one. That lasted about 2 months, and ~4K miles and then I got a P0420 code. So that was under warranty and I replaced it with a Walker aftermarket CAT which was supposed to be a match for my engine. At that time I also replaced both O2 sensors with GM ones. This lasted about another month and ~2Kmiles and it too throws the P0420 code.
My mechanic looked up the VIN and he says it desginates a California car. I live in NY. I wonder if I got a stock OEM CAT if it wouldn't throw P0420 codes because somehow it is 'better' and more efficient at cleaning the air to possibly a higher (California) clean air standard. Is that possible? (ie, if this was true, to stick with the Walker CAT would require a re-flash to a lower NY emissions standard? Grasping at straws here...)
More questions:
1) Is there a difference in power/sound between a Walker and OEM CAT? (Ie, any reason other than cost I might NOT want to go try yet ANOTHER CAT?)
2) Is there something else I should be looking for that would cause the cat to go bad quickly, or exhaust to be "extra foul?"
If I reset the code myself without doing anything else, it comes back on its own after about 200 to 300 miles. I've done that 3 times now on the lastest CAT-- 2 before taking it back to the shop and once afterward.
Lately my "low coolant" light comes on briefly in the morning when it's extra cold, but goes out after a few seconds. I did replace a head gasket last summer too, which in theory could have put some coolant in the gas, but I never noticed any white smoke out the pipes. I'm wondering how bad that would be, would it also have wrecked the CAT (or sensors, or something) and could it be happening again?
I'd rather not get an O2 sim for this simple problem if all this really means is that this cat isn't as effiecent as a OEM version. The car runs super and has 105K miles. Regular oil changes, good body and exhaust is solid otherwise. She's my baby and I want her to last a while longer.
Options? Ideas?
thanks,
Joe
Simple question: Is there a difference in CAT effeciency required to pass emissions test (ie, and not throw a P0420 code) between California cars and others?
Background: 2002 GA GT : 6 months ago my ignition wires were shorting causing unburned fuel to enter the exhaust. it fried and plugged my CAT so I got a new "universal" one. That lasted about 2 months, and ~4K miles and then I got a P0420 code. So that was under warranty and I replaced it with a Walker aftermarket CAT which was supposed to be a match for my engine. At that time I also replaced both O2 sensors with GM ones. This lasted about another month and ~2Kmiles and it too throws the P0420 code.
My mechanic looked up the VIN and he says it desginates a California car. I live in NY. I wonder if I got a stock OEM CAT if it wouldn't throw P0420 codes because somehow it is 'better' and more efficient at cleaning the air to possibly a higher (California) clean air standard. Is that possible? (ie, if this was true, to stick with the Walker CAT would require a re-flash to a lower NY emissions standard? Grasping at straws here...)
More questions:
1) Is there a difference in power/sound between a Walker and OEM CAT? (Ie, any reason other than cost I might NOT want to go try yet ANOTHER CAT?)
2) Is there something else I should be looking for that would cause the cat to go bad quickly, or exhaust to be "extra foul?"
If I reset the code myself without doing anything else, it comes back on its own after about 200 to 300 miles. I've done that 3 times now on the lastest CAT-- 2 before taking it back to the shop and once afterward.
Lately my "low coolant" light comes on briefly in the morning when it's extra cold, but goes out after a few seconds. I did replace a head gasket last summer too, which in theory could have put some coolant in the gas, but I never noticed any white smoke out the pipes. I'm wondering how bad that would be, would it also have wrecked the CAT (or sensors, or something) and could it be happening again?
I'd rather not get an O2 sim for this simple problem if all this really means is that this cat isn't as effiecent as a OEM version. The car runs super and has 105K miles. Regular oil changes, good body and exhaust is solid otherwise. She's my baby and I want her to last a while longer.
Options? Ideas?
thanks,
Joe