is there any problems with gutting a cat or using a pipe with the O2 sensors on it instead of a CAT on a obd2 system ?

i'm not sure how all this works..
but the second o2 sensor is there to "sense" the canges in air from the CAT in the exhaust ...nah?

so if there is not CAT ...the same ehxaust passes on both o2 sensors..
and they get the same result.. will the ECU or something try to correct something else cuase of that ?

would that cause any issue ?
is it performance wise to do so? or will the O2 sensor hurt the performance i would gain by removing the cat ?

anyone with experiences in that ?

tanx

 

If you remove your CAT or punch it out your car will notice and put up a Check Engine Light! The second O2 sensor is there to make sure the CAT is working properly and if it is removed then the ECU thinks it is broke, telling you to replace it.

Also, if you remove the CAT or punch it out and get caught you can get a huge fine! But hey it's your call. There is a way to trick the OBD II into thinking your CAT is still there and working properly, do a search on how to trick the OBD II and you will find a link that will show you how.

 

preformance wise though, putting in a test-pipe on an obdII car... what happens other than the check engine light going off?

 

Other than the annoying light, there are no performance issues.

 

really?!?!??!? can anyone verify that??? not that i dont trust u or nothing, its ju that i heard so much stupid stuff that could happen, do u hav a testpipe on an obdII ride?

 

Friend of mine was running a jdm 4-1 header w/ test pipe on his 00 Integra Type R, and only had a check engine light. VTEC still kicked in, car pulled like it always had w/ the exception of having to stare at that annoying light!
So, he got a reprogrammed ob1 p28 ecu, which has no 2nd o2 sensor or knock sensor pinouts, and the light disappeared!
Dont worry about it, just dont get caught if you live in CA!

 

trust me on this one.

 

Are shops allowed to replace the cat-back with straight through pipes on regular street cars? A friend of mine is having a new exaust put on, and is having the cat-back removed, it was the shop that suggested that....

 

aite.. so is my integra 00 ls obdII or what? any1 kno?

 

i read on a previouse post to wrap the o2 sensor in foil,and it worked for about a month and 1/2,but if the check engine light comes on and as long as its not in limp mode,no problemo

 

Here is a web site that will show you how to cheat the obd II for a test pipe. This is for a mustang but works on hondas also, I know cause I tried it. The only diff is the color of the wires for the Hondas, the sigs are the same though. If any one has any questions just let me know. http://www.eaton-design.com/mustang/mil/