1999 Pontiac Trans Am Computer Trouble Codes/New Cats?


Computer problem
1999 Pontiac Trans Am V8 Two Wheel Drive Manual 86,000 miles

Hey, so long story short, the 'service engine soon' light has been on for a while in my car, but i've known that it has had something to do with the catalytic converters. Anyway, I just bought a code scanner, and when I hooked it up to the car, it gave me the codes P0430 and P0420, which are Catalyst System Efficiency Below Threshold Blank 1 & Blank 2. Just FYI, one or both of the O2 sensors have recently been either replaced or checked, so they are good.

Also, 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, can I be fairly certain by looking at these codes that both catalytic converters need to be replaced? Or is there additional testing that is needed?

Also, are the cats on my car ones that I can replace by myself? I took a peek under the car, and it looks like one cat can be unbolted (i think, it was a quick peek, so I'm not certain), but the other looks like it is welded on (unless the bolts are very far down the pipe). Are these replaceable without welding experience?


Do you
have the same problem?
Wednesday, June 23rd, 2010 AT 10:40 PM

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