Ok, im prety much new to cars, never owned one till now and never tried to do anything to one until now, i recently added a cold air intake to my car along with a set of headers, now after i installed my headers everything was fine till about a couple weeks latter the check engine light came on, ive taken it to autozone to get it checked out and go the code p0420, the list of problems reads as follows, 1 catalytic converter malfuntion, failure possibly due to 2 3 or 4.
2. Engine missfire or running conditions.
3. Large vacume leack
4. Engine oil leakage into exhaust.
now i dont know what it can be but the car runs perfectly fine, at first i thought the 02 sensors didnt work but now i think ive proved that wrong cuz the guy actualy got a reading from the machine, so, can it just be that the car isnt used to reading the signal from the 02 sensors withough the cat converter or what, or how can i get rid of that dam annoying check engine light, any resposnes are appretiated.

 

1. You'll need to list what year/model/type car you have.
2. You might want to try looking through the FAQ's for header information.

 

oh **** sorry i have a 2003 honda civic lx

 

Did you install a CEL eliminator/ Defouler on your 2nd o2??

 

no sir, i did not

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by GustavoO &raquo;</TD></TR><TR><TD CLASS="quote">no sir, i did not </TD></TR></TABLE>
do it, click the link 'My build thread' in my signature i have done it, with some pix there and with some links- its about halfway down the page

welcome to 78

 

k, i just got done installing the defouler and the check engine light is still on
dont know what ellse to do so ime leave it like this for a while

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by GustavoO &raquo;</TD></TR><TR><TD CLASS="quote">k, i just got done installing the defouler and the check engine light is still on
dont know what ellse to do so ime leave it like this for a while</TD></TR></TABLE>

give it X amount of start up and it will turn off

but dont sit there and turn on and turn off the car

 

check engine lights dont just turn off like they did back with obd0 or obd1, with obd2 the car wants to make sure that for an X amount of cycles, the error it detected before doesnt come back. Until that happens the light will remain on. Once the light turns off, the computer will still have to code stored in non-volitile memory for an additional amount of time. Or buy a scanner with a CEL erase function.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by skipbarber &raquo;</TD></TR><TR><TD CLASS="quote">check engine lights dont just turn off like they did back with obd0 or obd1, with obd2 the car wants to make sure that for an X amount of cycles, the error it detected before doesnt come back. Until that happens the light will remain on. Once the light turns off, the computer will still have to code stored in non-volitile memory for an additional amount of time. Or buy a scanner with a CEL erase function.</TD></TR></TABLE>

 

unhook the negative cable of your battery for 10-15 minutes. afterwards, the CEL should turn off.

the CEL may come back on later on, but then it'll turn off again after a couple of miles. the defouler does not work for everyone. when i had my race header on, the CEL would turn on and off here and there, but the car ran fine. if you really want the light off for good, then get a CEL eliminator like previously stated.

 

ive tried unhooking the cable in the past and the light did keep coming back on, il try it though, you think maybe it would help if i put the non fouler on the top o2 sencor?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by GustavoO &raquo;</TD></TR><TR><TD CLASS="quote">ive tried unhooking the cable in the past and the light did keep coming back on, il try it though, you think maybe it would help if i put the non fouler on the top o2 sencor?</TD></TR></TABLE>

The primary oxygen sensor should feed information directly from the exhaust, so putting a fouler on it would alter the car's performance in a rather bad way. The Secondary oxygen sensor is the one that picks up information after the catalytic converter (which if you don't have one, should be reading some horrible numbers).

 

i did mine that way and im an Lx, soo get the 02 foulers... made by HELP! and widen one, and just install.... unplug battery wait 10 mins, and i was g2g!

 

well after putting on the non fouler and disconecting the battery for a while the liight went off, havent really had a chance to really drive it but its been a few days now and the lights still off. ive only driven it a couple miles, just from home to work, and back, so, fingers crossed. lets hope it stays off, thanks for your guy's posts i apreciate it

 

uh havent posted anything on this thread for a while, but what do you suggest i do matt cuz my car has been feeling a little off latley, im thinking it might be the intake filter cuz i havent clened it since i installed it like 5 months ago, but if the number thing is true what can i do, is there any way or any place i can take it so they can retune the computer to make it work with the headers?






Modified by toyomatt84 at 1:00 AM 6/6/2008

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by GustavoO &raquo;</TD></TR><TR><TD CLASS="quote">uh havent posted anything on this thread for a while, but what do you suggest i do matt cuz my car has been feeling a little off latley, im thinking it might be the intake filter cuz i havent clened it since i installed it like 5 months ago, but if the number thing is true what can i do, is there any way or any place i can take it so they can retune the computer to make it work with the headers?</TD></TR></TABLE>

Well, you cannot tune the stock ECU to deal with the aftermarket header. So, there's really no way to get around that one. Are you getting any CEL codes? If not, what kind of "offness" have you been feeling in the car? Is it sluggish or noisy? Or, is there any 'hiccups'?

 

um, i dont know what codes im getting now cuz i havent had it checked out, but the cel is off now, the offness ive been feeling is that it is a little slugish at times

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by GustavoO &raquo;</TD></TR><TR><TD CLASS="quote">um, i dont know what codes im getting now cuz i havent had it checked out, but the cel is off now, the offness ive been feeling is that it is a little slugish at times</TD></TR></TABLE>

When during the RPM range does it "feel sluggish"? If it's just the sound of the intake being louder without an increase of performance, then nothing is wrong. Bolt-on's don't provide any feasible power gains, just a change in noise creation.

 

yeah it does feel slugish but just at times, im not sure how to explain it but it just dosnt feel as fast as it used to compared to when i first got it...also i started to notice a slight kreeking sound, when im taking off in first gear, and when i reverse, is it time for a new clutch?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by GustavoO &raquo;</TD></TR><TR><TD CLASS="quote">yeah it does feel slugish but just at times, im not sure how to explain it but it just dosnt feel as fast as it used to compared to when i first got it...also i started to notice a slight kreeking sound, when im taking off in first gear, and when i reverse, is it time for a new clutch?</TD></TR></TABLE>

There's already a few threads on clutch squeak, so you can fix that with ease. As far as bolt-ons are concerned, you're probably just experiencing the typical let-down of the lacking performance for the bolt-ons.

 

hmm, well it was runing reall good and i felt better than before when i first installed them but yeah, im sure your right man. hey lol i dont mean to be a pain in the *** but is my car a Vtech, i dont think it is but for future reference can you tell me my exact specifications for my car, i have a 2003 honda civic lx sedan. is this a D17? and a Vtech?

 

you mean VTEC, not "VTECH"

since you have a LX, its not a VTEC motor. yes, you have a d17, but the EX's came with the D17A2 which is the vtec motor. you have the d17a1.

in terms of performance on our motors, dont expect anything unless you turbo it. our motors are really for good gas mileage and nothing more. your best bet if you want power is to turbo charge, swap, or do what i did and get another project car with potential.

with the mods that you've done you may feel that your car is "off" because you may have lost low end torque, but you gain it back a little in the top end. nothing is wrong with your car.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by GustavoO &raquo;</TD></TR><TR><TD CLASS="quote">hmm, well it was runing reall good and i felt better than before when i first installed them but yeah, im sure your right man. hey lol i dont mean to be a pain in the *** but is my car a Vtech, i dont think it is but for future reference can you tell me my exact specifications for my car, i have a 2003 honda civic lx sedan. is this a D17? and a Vtech?</TD></TR></TABLE>

All that information is listed in the FAQ's.