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New Cats? How to go about replacing

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Old Jun 24, 2010 | 02:29 PM
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Default New Cats? How to go about replacing

Car: 1999 Pontiac Trans Am WS6 with some sort of flowmaster cat-back system on it.

The SES light has been on for a while (haven't been driving it much though), and I knew it had something to do with the cats due to an earlier repair. Anyway, I purchased a code scanner (and had my mind blown that mechanics charge $90+ for scanning when the scanner only costs $45), and got the codes P0420 and P0430.

Just a side note (btw, i'm a bit of a noob, so I'm kinda learning as I go): When I ran the codes, the scanner gave me 4 codes, 2 for P0420 and 2 for P0430. The first was for P0430, and it had the 'freeze frame' light on for that. The second was for P0420 and it had nothing with it. The next to were again for P0430 and P0420, but they both had the 'pending' light on for them. Does this mean anything? Or should I just be looking at the P0420 and P0430 codes and not worry about the other lights?

Anyway, the car has expired tabs, and it needs emissions, and I have 30 days to email the new registration to a cop who pulled me over for expired tabs. Also, I'm planning on selling the car soon.

So by looking at these codes, can I be pretty sure that both cats are down? And what would be the best way to go about fixing this? They look like they're welded on (?), so i'm assuming i'll have to have someone replace them. Should I be trying to find used/aftermarket cats?

Thanks!
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Old Jun 24, 2010 | 03:04 PM
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First of all where do you live?

Second if you lucky what you can do is go to an auto parts store (o'reillys for example) and buy a "pass smog" bottle.

Trust me i just did my truck (03 silverado 5.3) and i had those exact same codes. And i put that stuff in the gas tank (nearly empty) and i ran the truck hard so the engine was HOT. then i cleared the code and went to get it smogged and it passed with FLYING colors!!!!

Worst case scenario you would have to put new cats on...

GOOD LUCK!!!!
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Old Jun 24, 2010 | 03:31 PM
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Hah, wow. Well I'll keep that plan as backup. I need to sell the car, and the SES lights comes back on after 5-10 minutes of driving after clearing the code, so I need a more permanent fix....i think.

I live in Washington State.
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Old Jun 25, 2010 | 02:24 PM
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Anyone? Are the cats something I can replace myself without welding experience, and if so should I be getting factory ones or aftermarket (and if aftermarket, which ones?). Again, i'm selling the car, so i'm not terribly concerned with performance/long parts life. As long as it gets the SES light off for a while.
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Old Jun 25, 2010 | 02:32 PM
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you can find somebody on this site buy used cats from, you want OEM cats and they will bolt in. You will need them from a 98 or 99 car.

you cannot buy used cats from a salvage yard, they are not allowed to sell them.

Factory cats are in the $500 a piece range (for 2000 parts, unsure on 98-99 prices)

Ryan
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Old Jun 25, 2010 | 02:52 PM
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I'm getting my cats replaced for free at the dealer. I believe as long as you are under 80,000 miles, cats are covered.
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Old Jun 25, 2010 | 03:36 PM
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I just took a pair off my 2000 T/A I'd sell you for $200 shipped. They just bold between the manifolds and the Y pipe. No welding required, but you better have some decent jack stands or a lift. PM me if interested.
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Old Jun 25, 2010 | 04:13 PM
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Are you sure those will fit on my car?

The reason I question is because I just read this:

https://ls1tech.com/forums/parts-cla...e-gaskets.html

Different cars, but is the same problem going to apply to me?
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Old Jun 25, 2010 | 04:17 PM
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I honestly don't know. I f you're interested in buying them, I can take some pics when I get home so you can see the flanges.
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Old Jun 25, 2010 | 06:21 PM
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Ya, if they'd fit, i'll buy them. Is the flange the only part that would be different? Anybody else know if these would fit?
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Old Jun 25, 2010 | 07:35 PM
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I have a set of cats off of my 98 Z28. Vengeance Racing took them off today when i put in headers and a catted TSP Y. PM me if interested. Thanks
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