Hey /o/ I have a question My 2005 honda accord lx has a very

>>13644515
Your cat is bad

>>13644529
Is it feasible to fix that myself or should I have a mechanic do it for me?

>>13644529
This and as long as u dont live in comifornia they are cheap to replace

Thanks guys, so far my first and best experience here!

>>13644553
can you weld? if not take it to a muffler shop.

my advice would be find a high flow CC yourself. if you are going to replace it, might as well gain a few horsepower.

>>13644564
>>13644529
A bad cat wouldn't impact the upstream sensor.

>>13644609
What would hurt the upstream sensor?

>>13644615
I doubt both are bad. Either one is bad and it's throwing the ratio off, or the cat is bad and replacing the sensors didn't do anything for you.

2005 is OBDII, do you have a check engine light? A code would help.

>>13644605
Can't weld but my brother can, what needs to be welded?

>>13644641 I had one this morning, went to auto zone and had a po420 and po139 or something, same codes for both o2 sensors

>>13644641
Also, the guy at auto zone said something was bad with my exhaust, I put some 02 sensor cleaner in my gas tank and the check engine light hasn't come back on and I've driven about 70 miles

>>13644656
PO139 is the rear O2 sensor, meaning the one after the cat.
PO420 means the cat isn't working as well as it should.

Probably a bad catalytic converter, your O2 sensors are likely fine. Don't just replace it though, take the car to a mechanic. Something else may be wrong that caused your cat to fail prematurely.

>>13644609
The code won't specify the sensor.
If both have been replaced then logic dictates that the cat is bad. This gives the downstream sensor a bad reading and throws a code.
Just went through this on my car

>>13644698
Oh okay, thought a 420 was just the sensor
Also, my car has 160,100 miles on it, lol

>>13644711
I feel your pain, I've replaced the rear one 3 times and just replaced both of them last week or so
I don't know why I didn't come here the second time it happened, this place is great!

Cadillac converter

>>13644724
>this place is great
This one experience will never happen again.
You're lucky you caught nice people. Go read the radiator cap thread.

>>13644743
True
But the advice here is great, sometimes the people can be shitty, but the advice outranks that for me