So after scanning my dlc i found p0420, i did a search and found that the cause of this dtc is either the main cat or the precats taking a dump ..


well since mine doesnt have a main cat , i'm guessing my precats are taking a sh*t, but how do i know which one?


ideally i'd like to find some used headers and get the 02 sim.

http://www.o2simulator.com/index.php...&products_id=9
anyone wanna give some advice?

TYIA

 

P420 would be first catalyst at the front of the car. Had mine replaced a about 3 years ago.

 

well i just did a quick search and found what i was looking for

P0420 = rear cat ( bank 1 )

P0430 = front cat ( bank 2 )



found a cat at a junkyard for $25 ....


i guess i'll take the cheap route and go with $25 since xmas wiped me out

 

gah!!

found out the " cat " they had for $25 was just the exhaust manifold w/o cat!!


anyone have any experience with this?
http://cgi.ebay.com/ebaymotors/2000-...Q5fAccessories



or should i just go with headers? The install i will be doing myself , but having a car down for too long isnt one of my best options

 

Whoa big fella.......there are other causes of a P0420 than just the main cat. Have you done basic troubleshooting and looked for exhaust leaks upstream of the cat, intake air leaks, plugs etc. I suggest that you obtain an FSM from one of the links on this website. Is this thing running perfectly irrespective of the P0420 code, or do you have any engine performance issues?

 

nope no performance issues, no other DTC's and i am getting around 420 miles per tank , and i do have the FSM handy .

no intake leaks , no exhaust leaks before the bank 1 precat and this thing has the stock precats still installed.

it has 142,xxx miles on it and reading most of the threads searched the main problem is the precats that go bad.

I dont wanna wait too long since the cat material can get sucked up into the engine


i also did a search and found this
http://www.car-stuff.com/carparts/ni...tings+Page%3A8


seems like the best deal so far other than replacing with headers and 02 simiulators

 

and just to clarify, this is whats causing my p0420 code





i hate cats!!

 

I have the same codes and considering getting headers as well.

 

i really wanted headers , but you also have to get the Y pipe and 02 simulators, which alone cost $80 + shipping..


not too many ppl selling used headers for our cars, otherwise i'd get some used ones and 02 sims...

 

well this is strange....i checked Alldata and found nowhere on there a precat for the Federal spec on the firewall side ???

now i'm confused?

The California spec has a front precat, but the other 49 state spec doesn't..is this right??


Can anyone clarify this please? I don't want to go and buy parts that i don't need ..

Just need to know if the rear cat, by the muffler and the California spec Maxima has the front precat, along the radiator side are the only cats on our cars.

 

Before you start throwing money and effort at that code, try running 2 cans of seafoam through the system, and using only Shell Premium gas. Reset the code. I did that, the code came on again in about 800 miles. Did it again, the code stayed off for 2000 miles. Filled up with Chevron supreme, the code came back.

Filled up with Shell, gave it a hard run on the freeway, the code went out by itself and never came back.


5000 miles later I totalled the car, da*n. 2003 3.5 Altima

 

well i did Seafoam my car a few months back when i 1st got it.

the kid before me had removed the rear/main cat and welded a test pipe up in place of it. But the strange thing is since buying it back in Feb. that code never came up until a few days ago.


So i was wondering if the main/rear cat is the only cat on cars made for outside of California ..

I know the CA. spec maxima has the front precat and the main/rear cat.