Misfires, Noises, Emisions, Codes!

[rymik444]

Few months ago I had misfire and code for both misfire and oxygen sensor. Had to drive home with it misfiring.

 

I narrowed it down damaged wiring at my upstream bank2 sensor... I repaired the wire and left the old sensors in.  Voltage was ok afterwards the codes went away.

 

However, at this time I was getting a rattling noise. I thought it was the converter, that maybe a piece broke off or it was damaged when I drove it home while it was missfiring.  However, I could not manually produce the sound while hitting it with hammer. After a few days, the rattling  went completely away!!!

 

I have driven it for about 100+ miles since and there has been no noise or codes. During that time, the only issue I had was that it rough idled after filling the tank for a few moments. This only occured once so I didnt think to much of it.

 

Today I get P0430, efficiency below threshold bank 2. No other code popped up and there is no noise and it appears to be running fine.

 

Do you think I should replace the sensors? Or is it likely the cat is bad?

Can you venture to guess why the noise which I thought was the cat completely disappeared? 

 

What the best way for me to diagnose if this is the sensors (which I can replace in my driveway) or if its the cat, (which I would have to pay to get welded properly)? 

 

Thank you.

 

 

[carnau]

2 minutes ago, rymik444 said:

Few months ago I had misfire and code for both misfire and oxygen sensor. Had to drive home with it misfiring.

 

I narrowed it down damaged wiring at my upstream bank2 sensor... I repaired the wire and left the old sensors in.  Voltage was ok afterwards the codes went away.

 

However, at this time I was getting a rattling noise. I thought it was the converter, that maybe a piece broke off or it was damaged when I drove it home while it was missfiring.  However, I could not manually produce the sound while hitting it with hammer. After a few days, the rattling  went completely away!!!

 

I have driven it for about 100+ miles since and there has been no noise or codes. During that time, the only issue I had was that it rough idled after filling the tank for a few moments. This only occured once so I didnt think to much of it.

 

Today I get P0430, efficiency below threshold bank 2. No other code popped up and there is no noise and it appears to be running fine.

 

Do you think I should replace the sensors? Or is it likely the cat is bad?

Can you venture to guess why the noise which I thought was the cat completely disappeared? 

 

What the best way for me to diagnose if this is the sensors which I can swap myself or if its the cat, which I would have to pay to get welded? 

 

Thank you.

 

 

What's the year make a model of the vehicle?

 

Without knowing those, here are a few things you can check.

A P0430 can be checked with a back pressure gauge. That's the best way to tell if it is a converter or the 02 sensor. I actually just picked one of these up to do a review on my channel and I actually like it better than my snapon and it's 100x cheaper. https://amzn.to/2WFcCyh

 

Also, Fix your cats. Don't cut them out. The truck works better with than without them.

 

The noise could have been a collapsed lifter if its a 2007+ AFM truck but without the y/m/m I am not sure.

[rymik444]

Its a 2000 silverado  4.8

 

Cant cut em', wont pass the test.

 

I will have to research the pressure test. However, if i have get the cats replaced, im guessing i would do the o2 sensors too at that time. So maybe it makes sense to just swap out both bank 2 sensors at hope that solves the prob.

 

Is bad cat and bad sensors the only causes of po430?