So this code has been on for quite some time now, sometimes it goes off then when it comes back when i start its a really rough start. I changed the o2 sensor that is in bank 2 right up front and it didnt make a difference and on my obd2 scanner app when i press "fuel system status" it says ecu1 5) closed loop:using O2 sensor but there is a fault and when i press O213 it says "Not used" Also sometimes a p0300 code pops up but not too often pls help

 

You replaced B2S1 oxygen sensor, (passenger side, upstream of the catalytic converter). P0147 is indicating there is a problem in the heater circuit for B1S3 oxygen sensor, (downstream of the catalytic converter). The problem, whatever it is, will not affect engine performance. The sole purpose of B1S3 is to monitor the performance of the catalytic converter.

 

Ohhh okay, I was seeing bank 2 and i thought that it would have been the bank 2 sensor. I guess ill change out the b1s3 o2 sensor and see what happens

 

My 99 blazer 2wd started code p0147 and my catalytic converter has been making some shaking noise inside of it. When I accelerate, I also hear a constant rattle coming from underneath. Could this just be then end of my Converter?

 

yep, converter is shot

 

Is there online sites that have them for cheap. Trying to find a direct fit just to not have to deal with the welding? Found a direct fit for $197.99 at AutoZone. Also how long can I run it before something goes bad I've been driving it for a bout a month like this already.

 

Try rockauto.com