Injen cat back exhaust with hfc throwing CEL.

P0420: catalytic converter system
- efficiency below
threshold (bank 1)

** need help getting rid of this problem. LMAO, I drive with a OBDII scanner in the car to delete the code after every drive cycle. Has anyone ordered from this site/ purchased: http://www.o2-simulators.com/?gclid=...FcvJKgodwQpwag

** I have an o2s spacer on right now, clearly doesn't work.

 

Mount different O2 spacer or on different position. This code is thrown by second O2 sensor after the cat.

 

I have the spacer on my ho2s (the hfc o2s). This is the second spacer I purchased. If I remember right, there is no sensor after the cat. There's three o2s:

1. There's a spot on my down pipe but is blocked off with a bolt.
2. One Before the cat
3. In the Cat

*See picture. This is my exhaust...

 

FED cars have 2 O2s, PZEV cars have one more.

From what I read you should have FED car and 1 free spot for wideband.

In case of FED car, ECU makes comparison between measurements of the O2 sensor before cat and O2 sensor after the cat. By doing that it can decide whether cat is working as expected.

In your case the last O2 sensor is in the end of the cat, spacer should be placed there. You should not put a spacer before cat.

 

correct, i have a spacer on the ho2s (the sensor that goes into the h.f.c.)

 

So, that should be fine.. did you asked Injen what spacer should be installed? They usually make tests of their applications, so they should be aware of your problem.

 

make sure you put the spacer on the one under the car that goes in the cat. sometimes its better to make your own. go on ebay and buy a set of 2 anti foulers. one of the antifoulers take a 1/2 inch drill bit and drill thru it. screw your o2 sensor into that one. then screw the other anti fouler on to it (don't drill this one) then screw the entire assembly into the cat. erase code and shouldn't come back. this is the only thing that would work on my 02 lancer after a header install. but i'm not sure how the newer models are set up. usually the p420 means that the pre-cat isn't working. it has to drop a certain voltage by the time it reaches the 2nd o2 sensor

 

thanks, bro! ill let you know what happens.

 

good luck man. keep us updated

 

has anybody tried the "Mini Cat O2 Sensor CEL FIX" from bigdaddiesgarage? i came across it on google when trying to fix the p0420 everybody else is having. do you think it actually works..

 

Never heard of it. I'm getting mine off of "O2-simulators.com". I'll take a look though. When I get mine, I'll let you know.