i know this is a NISSAN site but still try to help out a HONDA owner

[kpariaug]

my friend has an 00 civic w/ a d16 engine. we put on an aftermarket cat and headers.

the o2 sensor cant fit at all in the hole on the cat towards the back because of the shifter touchin it really hard. there is a hole on the front so we just threw it there for the sake of havin the o2 sensor back in.

prob is the check engine light is on and the code says sumthin about o2 sensor (nuthin specific). and gas milage is BAAAAD. plus loss of power.

so think we can jus plug up the holes and drill a new hole on the cat towards the rear bottom to clear the shifter. or does it need to be a certain depth, and blah blah blah...

again, i am really sorry about askin bout a honda in a 240 forum but please give us some ideas. and please no smart @sses. THANKS!!!

[mr2man07]

loss of power? i didnt know the d16 had power in the first place

you can drill a new hole. there are bungs at exhaust shops that will fit the o2 sensor threads, cut a hole and weld the bung in there.

[TRBOMOFO]

most of the time when you do these kind of modifications you will get that check engine light on with hondas cause when all my buddies do exhaust changes they get the check engine light on

and the CO2 sensor might be bad and i would have to sit and think exactally whats going on but i would think as long as the sensor is in the system it should be alright

and make sure all the other holes you had are plugged off

[AZhitman]

Any chance you could just flip the cat over so the bung is facing the other way? Might have to extend some wires...

Also, you can "extend" the bung so that the sensor is a little "backed out" of the hole, and that will sometimes address the issue as well.

[kpariaug]

we cant flip it around the ends are different so it has to go one way. and all the other holes are plugged off.

im guessin we'll jus take it to an exhaust shop.

thanks for the advise and if anything else hits you let me kno.

[IslandStyle]

A Die Hard Hondahead myself (but I daily drive a 240) - the second O2 sensor only reports to the ECU that the catalytic converter is working efficiently. If it is reading too much co2 then you will get a check engine light. However, the catalytic converter's o2 sensor (called the secondary sensor) really shouldn't affect your gas mileage at all. That's usually caused by a dead/damaged PRIMARY o2 sensor which is the one in the header. Gas problem aside, to solve the catalytic o2 sensor "in the way", yeah you can definately move the location- HOWEVER, move it furhter towards the back of the catalytic converter but keep it as close as possible to the original location without bumper your shifter.

For the record... my Civic is currently running an all motor B16 setup that blows right by my best friends SR20DET without any effort LOL! But I have an LS/Vtec in the works too... but welcome to the NICO forums!!!

[kpariaug]

thanks for all this info. it looks really good. we'll check out the first 02 sensor. thanks alot.