I'm throwing a P420 code and my car doesn't seem as powerful as it once was. What are some of the symptoms of a bad Catalytic Con?

 

From http://www.obd-codes.com/trouble_cod...old-bank-1.php

Try to reset the code and see if it comes back. Check/replace A/F senor. Then replace the cat. If you have 99 TLP and less than 80k miles, cat is covered under federal emission warranty.

Let us know what you found out. Hopefully it is not the cat. I have an used one if you need it.

 

If the cat were real bad then yes there would be less performance. As for signs, not really. You could get under the car and tap on it and listen for rattles.

I would have it retested by someone with a good reader/dealer to see if any other codes are stored with it. it could actually be the O2 sensors causing that code.

 

Yea, I had the dealer scan it about 4,000 miles ago and it came up and they quoted me about $800+ to replace the cat. Well at the time I was throwing the clogged EGR code also which they wanted to charge about $500 to fix. Anyway, I cleaned my EGR myself as I have done before with your help and cleared the codes. That was about a month ago. Well after about three weeks the check engine light came on and its reading that it's the cat again so I assume the dealer was right. But my car is also not as peppy. Doesn't accelerate like it use to and sometimes it idles a little weird when first turned on. The idle dips really low then it jumps back to normal.

TunedTL, yea I have a standard '99 tl. How much you willing to part with the cat for?

 

Just PMed you, the new cat is around $750. I installed a Type S cat since I want to use Comptech B pipe. I used a flash light to exam the TLP cat I took, I can see light coming out the other end so it is in good shape. Let me know if you need pictures.
BTW, cat is really easy to take off, just 6 flange bolts, 3 on the inlet, 3 on the outlet. Unscrew the AF sensor and put it back on the new cat. That is why dealer charge you $800 mostly for part, not labor.

 

You can also look into aftermarket cats too that are like 200 or soo.

 

See thread
https://acurazine.com/forums/showthr...6&page=1&pp=25
Random Technology has a cat for $225, but you need to extend the A/F sensor wires by 6" since they put the sensor bung in a different location, stock wire won't work. I am in Cali, did not go for RT since it is also not CARB approved.
Does anyone know Magnaflow is a bolt on or a weld on cat?