Gutted Cats

00sentra · Feb 14th, 2003, 03:17 PM

I recently gutted my cats and it threw a code about two days after I did this....I have performed a search on the site to find some info but I came up empty handed....any help would be greatly appriciated.

Feb 14th, 2003, 07:17 PM

where where the cats, If its a 2000 or newer get ready to spread the cheeks.

Feb 15th, 2003, 01:15 AM

Well your O2 sensors are now reading raw exhaust, top and bottom are getting the same readings, because you no longer, have a cat anymore. The SES is mainly an emmissions problem hence thats what it thinks is going on. You should be alrigth. But the only way it will go away is with a new header. If you gutted them I dont think relocating the sensors will get rid of it, someone else should speak up...............I know they could shed more light on the subject.

**chimmike** · Feb 15th, 2003, 07:55 AM

Pdid got it.

myoung · Feb 15th, 2003, 08:37 PM

yup....pdid..

my question would be why did you gut it in the first place? todays cats are free flowing and probably didn't gain you very much at all, except this headache....plus why be a gross pulluter for 1 hp?... Gutting cats is old school... from days of yester year when cats were really restrictive.. buy a Random Tech cat and make your 02 sensors and ecu happy again...

Feb 16th, 2003, 08:57 AM

You could find out what the oms are supposed to be and buy a resistor. Maby, heavy on the maby. How does the header alone make the light go away. I'm going to build my own header. I was going to go with the resistor trick and a xxxx box to read the
air fuel mix.

**chimmike** · Feb 16th, 2003, 12:57 PM

the resistor thing might be a little difficult, but it can be done. Or you can relocate the sensor past the main cat.

also...........vari.........I'd also suggest building a secondary if you're building a header too.

Feb 16th, 2003, 07:29 PM

Sorry mislead you, I was reading some where that a air fuel meter could be put in the works. It has its own O2. How many cats do they have? I thought that it was in the exh manifold.

KSipmann · Feb 18th, 2003, 09:17 PM

Again, as Mike stated "my question would be why did you gut it in the first place?"

00sentra · Feb 20th, 2003, 02:02 PM

I gutted the cats cuz it was free, and considering that the motor was rated at partial 0-emission I thought the cats would be extremely restrictive. I was also wondering if I could run an inline resistor that would allow the ECU to register the proper voltage per stock settings. Just so you know I feel more torque but its in the higher end....I did manage to lose a little low end. Thanks for all the input guys.

**chimmike** · Feb 20th, 2003, 04:18 PM

yeah, generally on mods like that, if you gain, you lost some somewhere else.

on the resistor, if you can figure out what voltage resistor you need, it would work.

00sentra · Feb 20th, 2003, 04:20 PM

does anyone know the voltage that the o2 sensor returns to the ECU???

Mar 5th, 2003, 07:41 PM

How many cats do they have? Where are they? Thx

**chimmike** · Mar 5th, 2003, 07:54 PM

how many cats? the "cat" on the manifold is just a collector from what I gather, the main cat is where it normally is.........under the center of the car.

Mar 8th, 2003, 10:14 PM

I'm still lost as all could be. Will the Hot shot throw a light? Is one of the cats in the ex. manifold and just be hind the secondary? Could he buy a aftermarket high flow and relocate the sensors. I read the aricle in Nis Per Mag and they did not say? They located the bottom two O2 in the secondary.