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REDGTSFURY
03-13-2009, 01:25 PM
So just the other day my check engine light came on so I took a trip to advance auto parts and got a free c.e.l. diagnosis and it pulled a code p0420 catalyst below par, so I was told that I might need a new catalytic converter(and the car has been feeling a bit sluggish) so I was wondering what other types of catalytic converters are on the market that I can purchase, racing cat if possible, or even a nice hi-flow would do nicely,(or is the car REQUIRED to have tha factory 3-way cat) any sugesstions on this people?

Galcobar
03-13-2009, 11:54 PM
It must be the three-way catalytic converter -- you cannot degrade your emissions equipment. If you cannot find a direct-fit converter for your engine, you need to match the style of converter and its maximum engine size to your car (e.g. TWA w/ air, 6.2L will work for your 1.8L). That said, a quality converter in good condition has almost no effect on exhaust velocity. And I thought the seventh-gen used TWA with air converters.

However, the big issue I'd raise is why your nine-year-old catalytic converter failed when you've got cars on this site with twenty-five years and 300,000 miles who run the original converter. Figure that out, or you could be looking at a replacement not that far down the road.

As for prices, hottexhust.com and justmagnaflow.com are the best I've seen for Car Sound (parent company of MagnaFlow).

alltracman78
03-14-2009, 01:10 AM
The 25 year old cars don't monitor the cats. They're probably degraded well past the point of failure.

OBII [96 ^] have an O2 sensor after the cat; the ECU compares it's signal to the O2/A:F sensor signal before the cat. If certain conditions aren't met, it will set a code.

Hard to tell if it's the cat or the O2 sensor. What I would suggest you find out first is if it's still under warranty. I don't remember which years specifically, but some emissions parts have 8 yr 80,000 mile warranties.

If it's not, your next step is either throwing parts at it or having it diagnosed somewhere. This is one code you need a scan tool to correctly diagnose [not just a code reader, you have to see the actual information].

Galcobar
03-14-2009, 09:59 AM
The car may not monitor the cat, but emissions testing does.

REDGTSFURY
03-14-2009, 12:17 PM
Yea, like I said, I took it to advance auto so thats is the info they gave me. My celi has a little over 115k on it, it did have a few problems before I got it(everything from a cracked trans casing, to loose motor mounts and other "little" things! lol)but I took care of everything else and this is probably the last setback I need to fix up, maybe the cat had a little run in with the last owner...hmmm :sneak: ? Thanks for the exhaust websites, I will have to check them out. And as far as warranty info goes, I guess I will pay the dealer a little visit later, hopefully some type of coverage is in order, thanks fellas.

alltracman78
03-14-2009, 11:43 PM
The car may not monitor the cat, but emissions testing does.

Tailpipe tests aren't as picky as the OBDII programming is.

You don't even necessarily need a cat to pass tailpipe; my 85 22R with no cat, no emissions equipment whatsoever and a larger carb passed on the rollers [harder than 2 speed idle] with flying colors [we use CA emissions where I live too].

The Captain
03-15-2009, 08:47 PM
I have a Random Technologies metal substrate free flow cat. 3inch. Love it. Pass every time!

wizzards581
03-15-2009, 09:03 PM
The 25 year old cars don't monitor the cats. They're probably degraded well past the point of failure.

OBIII [96 ^] have an O2 sensor after the cat; the ECU compares it's signal to the O2/A:F sensor signal before the cat. If certain conditions aren't met, it will set a code.



today we are still using OBD2...

alltracman78
03-15-2009, 11:45 PM
Yes we are, that was a misprint.