Nissan Forum banner

1 - 8 of 8 Posts
G

·
Discussion Starter · #1 ·
i put a hot shot header on my car, as well as the down pipe a high flow cat and a muffler. my check light came on and it point to the cat. how can this be everything is new, no sensors are bad, the code checker says its the cat, maybe i dont have enough back pressure. any ideas?:confused:
 

·
ex-Super *********
Joined
·
1,410 Posts
Did you remember to put the second O2 sensor behind the cat?
Also what kind of high flow cat is it. Some are junk and dont work well enough for the ECU to like.
 
G

·
Discussion Starter · #3 ·
2nd o2 sensor? i put the second one in the place for it on the down pipe, but their isnt one after the cat, not even stock was one behind the cat. i got the hi flow cat from a local mufler shop. i am just out of ideas.
 

·
ex-Super *********
Joined
·
1,410 Posts
Does your car have 2 O2 sensors?
If it does then when it was stock there had to be one before a cat and one after a cat. Thats how OBD II works. Im not "up" on B15's all that much, but how many cats did your car have and where were they. Could there have been one that is part of the exh manifold and one under the car? So the header has 2 O2 fittings? I have seen this before, and its a weird situation.
Was your code for catalyst effiency? Trust me the rear most O2 sensor must be relocated behind the cat.
 
G

·
Discussion Starter · #6 ·
i have 2 o2 sensors,stock - one on ex manifold and one before the cat, with header - one on header and one before the cat, i got a fitting to be welded on to a pipe and it came with a bolt, i guess to plug something off. i am going to read it again then post the code i am getting.
 

·
ex-Super *********
Joined
·
1,410 Posts
With the header you need:
One on header and one after cat. Just like in that link I posted above.
The fitting needs to be welded behind the cat and the bolt should plug off the one before the cat.
 
1 - 8 of 8 Posts
Top