Update: P0420 ---- first time i have ever heard of this

[bRaZEn_407]

Taken from UrbanDictionary


1. /thread

This gets used on messageboards / forums to signify that the previous post (or a post that has been quoted) is either of such high standard / very useful and answers the question of the original post / owns someone that the thread cannot possibly contain any post that's better.


USER 1: Hey guys, who do you reckon is the greatest rock band in the world.

USER 2: Black Sabbath

USER 3: /thread

 

[soccerchamp16]

Taken from UrbanDictionary


1. /thread

This gets used on messageboards / forums to signify that the previous post (or a post that has been quoted) is either of such high standard / very useful and answers the question of the original post / owns someone that the thread cannot possibly contain any post that's better.


USER 1: Hey guys, who do you reckon is the greatest rock band in the world.

USER 2: Black Sabbath

USER 3: /thread

Oh.. got it!

 

[soccerchamp16]

Okay, so for those who have not followed my posts on other P0420 threads. Here is a long story short.

Replaced (in order)
both o2 sensors
ALL SPARK PLUGS
throttle body gasket
EGR gasket
PCV valve and grommet
Lastly...Cat Converter (with a magnaflow)


cleaned (in order)
Throttle body
IM (gasket looked fine, didnt replace)
EGR (sprayed TB cleaner, not too much)



Check engine light came back on but goes on and off, but car runs fine.
The other day I cleaned my car, and took off the plastic engine covers and pulled the fuse to reset CEL. I drove my car the rest of the week (CEL usually would come on within 20-30 miles.) and the CEL did not come on. It hase now been 115 miles. So, I thought that was strange. Then i realized i forgot to put my engine covers on. the only one that i didnt take off, was the one that is on the front (near oil cap). all others were removed when i cleaned the car. anyway, i thought that maybe i had a vacuum leak, and my engine covers were trapping the fumes, and the vacuum leak would suck it up, causing the p0420. so at 115 miles, i put ONLY the middle cover on (goes in between the cylinders, by fuel rails). My light came on at 134 miles. WTF!!!! does this mean its a vacuum leak somewhere?

If you want i'll make DIY thread for this but there are several on youtube

 

[619rcr]

If you want i'll make DIY thread for this but there are several on youtube

So, what you've learned is Magnaflow doesn't work unless you treat it like a straight pipe? thats what I get from all of this. Why run a cat if you gotta use antifoulers to make your code go away. You could've just ran a straight pipe with anti foulers. Right? Or did I miss something?

 

[soccerchamp16]

So, what you've learned is Magnaflow doesn't work unless you treat it like a straight pipe? thats what I get from all of this. Why run a cat if you gotta use antifoulers to make your code go away. You could've just ran a straight pipe with anti foulers. Right? Or did I miss something?

Yeah, some people don't like the sound with a test pipe. I like the sound of my car right now, later on I might gut the cat but I don't know. But some don't even get the code to start with.

 

[619rcr]

Yeah, some people don't like the sound with a test pipe. I like the sound of my car right now, later on I might gut the cat but I don't know. But some don't even get the code to start with.

I got my test pipe for $15 off ebay. I lost my Catalytic converter somewhere in the garage. I wouldn't gut the cat. I did that on my 240 in high school. It sounded stupid. I dunno why, but the test pipes seem to work better than gutted cats.

 

[soccerchamp16]

I got my test pipe for $15 off ebay. I lost my Catalytic converter somewhere in the garage. I wouldn't gut the cat. I did that on my 240 in high school. It sounded stupid. I dunno why, but the test pipes seem to work better than gutted cats.

What most do is gut the cat, continue the piping through the cat and put the cat on over the piping to make it look legal but in reality its all a straight pipe.
How does your test pipe sound?

 

[619rcr]

What most do is gut the cat, continue the piping through the cat and put the cat on over the piping to make it look legal but in reality its all a straight pipe.
How does your test pipe sound?

My test pipe does seem to make the car a little louder, but I also have a header. What you described to make the car appear legal sounds rediculous. Having previously lived in CA, and being pulled over for loud exhaust. I'm happy that AZ doesn't seem to care about what people have done to mod their car as long as you have no codes. Just for example Diesel's here run those stupid stacks in the bed & can blow clouds of smoke & still pass emissions. It's unbelieveable. There is no visual inspection at all. I drove my other car thru emissions recently with a header that eliminated the stock 3 cats & passed with flying colors.

 

[soccerchamp16]

Yeah see that would work for you but here in Texas I can't get away with all that. I just passed inspection yesterday. We have to have a cat and a muffler. We can delete all but one cat and delete out resonator but we have to have a muffler and a cat. I like the sound of mine, it's real loud too I got a noise complaint the other day in my neighborhood...

 

[LowerMyCG5]

imo v6 especially the j32,35 guys can get away with a test pipe or no cat. us 4cyl guys cant unless you run a test pipe and a really good resonator like vibrant ultra quiet to a muffler like a ws2 or magna flow.

my friend has no cat, race header, 2.5 piping to a vibrant ultra quiet and megan racing dual tip muffer, and the car is so damn quiet at idle and up to 4k. even past then its not loud