ForeignPolicy

Hey, Put a brand new bright and shiney HP raning header on my car. Guess what it has no 02 sensor for the 2nd o2 and my car runs like crap. We are all fussing weather or not its back pressure or the 2nd o2./ Any biody gots any help opn this ???.

Evs-One

Not having the o2 sensor won't be that noticable. Your car will usually just run a little richer and you'll suffer in gas mileage, but it won't be that critical performance wise. Doesn't your 2nd o2 sensor plug into your cat?

Civic242

just advance your timing a bit and this should stop the stalling issues.

==> http://home.mpinet.net/t-hero/Headers!!.htm

sohc_boy

on the 96 up dx's the cat is part of the exhaust manifold. either add an o2 sensor bung for the 2nd o2 sensor or get an o2 elinimator/simulator.

ForeignPolicy

ok, I have adsvanced my timing, reset my ecu and put my baffle for my muffler in, It still doewsnt run as strong as before, could back pressure be the problem??

madhatch

bump! If its back pressure then why have a hi flo cat?

ForeignPolicy

bump, anybody got an answer?

BlackDeuceCoupe

Are you throwing codes???

ForeignPolicy

2nd o2 but I dont know how to read Honda codes, Mostly A VW and old shcool shop just coming around to the honda movement

99DXcoupe

I got a dx also and when i got my headers installed theres was no hole for the 02 censor so i dont have it u wont feel any difference but is true that is gonna run lil but richer

madhatch

I felt a difference and everyone told me it was loss of back pressure, But i have not ran it at the track so It may just fell slower, I love the header, easy install and looks great.

cre18

what brand headers are you guys running with your d16y7? and what do you end up doing with your second o2 sensor?

Civic242

Can't be back pressure. I dropped a full second on my 1/4 mile time when I ditched my OEM header w/Cat. Your car is stronger with out the OEM cat but your CLE will light up.

sivik2nr

the header has no hole for an O2? or ...? if your header has no hole go have a bung put in and put that o2 in the hole..

plug up that hole son!

scttydb411

is it 96-00 dx? it sounds like you have ex header and dx catback. you won't have secondary o2 sensor. i have dc header and the primary o2 is at the end at the collector and i added hiflow cat that has the secondary at the outlet and ex catback. if your header has primary o2 up top just get someone to weld o2 bung at the header outlet. i assume valdosta doesn't have emissions testing. you'll probably fail if you are not running a cat. mine has bog right after start up at light throttle, but goes away if i open it up. only get bog on first pull. never thrown a cel. after that no probs unless i turn off car for few minutes or longer and restart. car pulls a lot better though. i was told i might be running a little lean and the obd2 is compensating for more air fuel (running aem cai) that's why mine goes away. going to tune up up and poss do something for a little more fuel. hope my ramblings help.

madhatch

Its actually my car, I will be running it in tonight, friday in douglas ga, we have about 40 imports going up and I will have an acurate read of weather i lost power or if it is just smoother, it "feels" slower but I did spank a jetta the other night pretty good coming out of 2nd which is my worst area.
I will post my times with it I got 10.8 last time with the same setup- the header.
It seems to strengthen the Nitrous at the lower end so I will be running it on the track for the first time hooked up also.

zelifcam

Uh? You guys are running without O2 sensors? That will open-loop you know... Not good for performance, not good for mileage. The ECU reverts to a "safe" default fuel map and behavior and will not modify itself based on actual engine conditions. I wouldn't bet on VTEC working either. Take the header to a machine shop and have the header drilled, and the proper threaded bung installed, preferably where it is seeing exhaust from more than one cylender. My oxygen sensor lies in the exhaust stream 1" before the catalytic converter. An oxygen sensor is not something you just want to leave out. So much of the ECU's logic revolves around it's input.

sohc_boy

aka limp mode

Civic242

Limp mode?? I ran a 16.220 @ 84.49mph with the same HP header on my 96 DX, with only the primary O2 sensor contected to the Header.

sohc_boy

and u probably would have done better than a 16.2 with the 2nd o2 sensor in place

ForeignPolicy

my car ran 11.4 in the 8th, .5 slower than before with smaller tires, so I do believe it is in " limp mode" I usually hit a 10.8 HP according to Import Tuner magazine has the best header available for the DX motor.

THanks