2005 LS8 sport catalytic issue/belt noise. (New Member)

[Chase4534]

I just bought an 05 LSV8. It was a repo that the people who defaulted hid in storage for over a year. It has 47k mi on it and I got it at auction for 8200$. It's one of the cleanest 05's I've seen probably due to the time it sat. When I got it one coil was bad, bank 2, I bought 8 new coils and plugs and replaced them fixed the misfire issue. Now I'm not sure how long it was driven with the bad coil but it was enough to throw a CEL p0420 bad cat code probably dumped enough unburned fuel into the cat to cause the sensor to read it as bad. It runs and drives fine but the cel bugs me so I gotta fix it. Most likely looking to do direct fit and replace both cats. Need suggestions on a few brands, flow, mag, east etc I want to fix the issue and get something that adds some performance. I'm going to do a mag cat back and cold air after I fix the cats and the CEL stays off. Also the belt has really been chirping lately I'm sure it just needs to be changed due to it probably being the original belt and the LS has 47k on it now but if anyone is familiar with this belt noise please chime in. I appreciate the help.

 

[jjcool00]

Nice grab, yep p0420 and misfires sounds like bad cats to me. Walker is a good brand people have had success with and Magnaflows. Both are direct fits. Belt you can just replace. I've heard the idle tension pulley has been known to cause some sounds similar to what you're experiencing.

 

[joegr]

...Also the belt has really been chirping lately I'm sure it just needs to be changed due to it probably being the original belt and the LS has 47k on it now but if anyone is familiar with this belt noise please chime in. I appreciate the help.

You very probably need to replace the tensioner assembly as well as the belt. Also, check and make sure that coolant isn't leaking onto the belt.