d16y7 - Exhaust Help

[97CivicDX]

Warning nOOb here, got my Honda and I like! 97 DX y7, was a gift so (wasn't going to turn down a free car) It had a cracked exhaust mani, shot cv's, a bad motor mount and the usual maintenance stuff. Almost done with everything but the motor mount, that's next.

The problem I am facing now is that I replaced the stock exhaust with a Holly 4-2-1 and a complete Tanabe Medalion catback, I got a hi flow cat straight from Japan (friend was there and mailed it to me thought this might have to go) after I installed the CEL came on and it smells like it is running rich, any help would be great!
:IHI:

[xxbrualxx]

whats the code?...i got a CEL from installing my header and new cat as well...turned out primary O2 sensor had failed...replaced it...and it was all good....thats the most common problem regarding CEL and new header install

EDIT: exact same Y7..but from a 2000..doesnt make a difference...so im guessin its ur O2 sensor

[myHonda1]

i'm say o2 as well, when me and my brother did this swap we replaced everything with new parts. no issue's.

[97CivicDX]

I'll get the code and post them up later, will stop and price new o2's I heard wide bands are better but will cost alot more! Thanks! also, how do you adjust the fuel mixture (smells rich) or will the o2 fix that?

[SOHC_STUDENT]

Unplug your negative battery cable for 10 min to reset the short and long term fuel adjust. From there the car should "relearn" how much fuel to spray with your new exhaust.

[evilkid187]

i have a '96 dx and i threw on a completley new exhaust header and all. im not even running a cat, just 2 resonators, but i have an o2 in the resonator and i don't throw any codes, never did. i did replace both o2 with brand new ngk ones i bought off ebay for like $50 a piece....i agree with everybody else, must be the o2.

[xcthc]

whats the code?...i got a CEL from installing my header and new cat as well...turned out primary O2 sensor had failed...replaced it...and it was all good....thats the most common problem regarding CEL and new header install

EDIT: exact same Y7..but from a 2000..doesnt make a difference...so im guessin its ur O2 sensor

hey dude, you ever figure out that rattling at 2500-3000?

[dkid15]

Are you sure its a high flow cat, because sometimes people confuse high flow cat and test pipe. THe high flow cats are still legal because they use platinum and radion elements as catalysts to break you exhaust down into legal emissions. Also my dad and me have a 96dx that i daily drive, i got a new exhaust manifold and 02 sensors and ignition system becaus ei guess there was a recall. I dont know about the motor mount though, you might want to upgrade and do new bushings. Good luck
+1 for making me think.

[xxbrualxx]

hey dude, you ever figure out that rattling at 2500-3000?

the rattling or raspiness?..i had some rattling from my secondary O2 in the cat..i ddint tighten it enuff:hammer:

but the raspiness...is all gone..i had a permanent resonator welded in...sounds a SHITLOAD BETTER...now i dont even drive with the bolt-in resonator...no more raspiness...and with the new Y8 mani....sounds NASTY..i should take a new vid/sound clip...ill do that and post it up sometime...

as for the 97civicdx...keep us posted on the issue...i think the running rich is from the faulty O2 sensor..but yeah...reset ur ECU by diconnecting the battery...then give her a good drive...WOT..and regular driving...just so the ECU can relearn like said above....u should be okay...

[gearhead98]

when i put on my headers, exhaust, and racing cat, i didn't replace my primary o2 because it was only 6 months old, but my secondary i kept. i am also throwing the a light, pretty sure it is from the secondary. i tried adding a mil eliminator, the spark plug non-fouler type, still got a light. tried another type of mil eliminator, still got a light. i got a post about it in the general tech forum. here (http://www.d-series.org/forums/showthread.php?t=63683) it is.

[sql_civic]

Get the code. Everything else is just a wild ass guess.

[christopher_davis]

my 96 lx has the exact same thing, would replace but doing a motor swap

[xcthc]

the rattling or raspiness?..i had some rattling from my secondary O2 in the cat..i ddint tighten it enuff:hammer:

but the raspiness...is all gone..i had a permanent resonator welded in...sounds a SHITLOAD BETTER...now i dont even drive with the bolt-in resonator...no more raspiness...and with the new Y8 mani....sounds NASTY..i should take a new vid/sound clip...ill do that and post it up sometime...

nice. i'm hoping the raspiness is my "hi-flow" (resonator) cat. can't wait to get rid of that thing.

[97CivicDX]

OK went AutoZone to use the OBDII scanner, reported code P0141 o2 sensor 2, bank 1 malfunction in heater circuit. Could this be caused by moving the sensor from after cat to before cat or do you think the sensor went bad. Also would you recommend cutting and splicing longer wires to make it after cat? The OEM would not reach thats why it is at the end of the header. Thanks!

[xxbrualxx]

hrmm im not sure..but i do think that code is from the secondary O2 sensor being b4 the cat...i beleive u do have to extend the O2 wires...id say extend..then reset ECU...and if u still get a CEL..then buy a new O2 sensor

[97CivicDX]

hrmm im not sure..but i do think that code is from the secondary O2 sensor being b4 the cat...i beleive u do have to extend the O2 wires...id say extend..then reset ECU...and if u still get a CEL..then buy a new O2 sensor

That's what i am gonna try Thanks! Hopefully it will pass emissions. :skull:

[xxbrualxx]

That's what i am gonna try Thanks! Hopefully it will pass emissions. :skull:

haha i dunno about that..i still havent had my emissions test since the new cat..and header install...lol...ima do a seafoam treatment for sure probably 3 or 4 days b4 i decide to go for emissions...

good luck..hope everything pans out

[97CivicDX]

OK, fixed, but I didn't move it, I was going to and was inspecting the wires to figure out what gage I should get, when I spotted what looked like tape part way from the plug.
Huh someone (a previous owner) had spliced the plug on the O2 sensor already, one of the ground wires had come loose (only twistd and taped), I put crimpers on them, reset the ecu and what do you know! no more CEL, Whoohoo!!! I will do a seafoam and take it to the emissions for inspection. The high flow is brand new so it should pass, update you later! Thanks!!!

[evilkid187]

that's crazy someone already spliced it....when i did my exhaust and put 2 new sensors in, i said fuck splicing, cuz i don't feel safe crimping and twisting... and bought an extender so my 2nd o2 would fit in the back of my high flow cat(really a resonator) and i havent thrown a code yet!...glad it worked out for ya though