imported_OneBadEk

I just did my emissions test and failed. I have a 98 hatch, and the cat is part of the headers. I put in aftermarket headers in last year and saved my old headers and cat. When installing the new headers, there are two sensors that need to be connected to the headers. One was bypassed and one was connected.

Anyway, I recently re-installed my old headers (which has the cat) back on to my car. None of the sensors were attached to it (I had the "check engine" light removed so I could get the test done). I drove the car with the old headers for 4 days and took the car for the e-test and failed!!!!

ASM 2525

HC ppm: limit - 76, result - 85 FAIL
CO %: limit - 0.42, result - 1.95 FAIL
NO ppm: limit - 580, result - 375 PASS
Gas Cap - PASS

Curb Idle

HC ppm: limit - 150, result - 70 PASS
CO %: limit - 0.70, result - 0.53 PASS
NO ppm: N/A


Do you think it has anything to do with none of the sensors being connected?? I'm an amateur when it comes to emissions. They connected a cable to my car's computer (since it's a 1998), and the computer can show that the sensors are not working, which could result in the failing grade. What do you guys think??

I did the usual oil change, run the highest octane for a week, put fuel injector cleaner in the most recent tank of gas before the test, and still failed. I don't want to spend an arm and a leg to get the car passed (I hear sensors are really expensive).

Thanks,

OneBadEk

PS - does anyone know where I could take my car to get it *cough* "passed?" I would greatly appreciate it!!

imported_BoOsTd

well the reason you failed is because the 02 sensor is missing/unplugged, which is sending a signal to the ecu createing a default setting, in turn createing a rich mixture and blowing fuel out the tailpipe, which is horrible for emissions... So you should conect the 02 senors back up and retry, gaurenteed pass, unless you have other major problems...

Its easy to do, if you can screw in a lightbulb, and plug in a toaster, then you can do it yourself... but the problem is you went and had the ecu tricked to shut off the check engine light , so now you wont know if the 02 sensors are actually working again..

So either have the ecu put back to normal, or go get the the codes read after you reconnect the 02 sensors to see if they are working...

imported_BoOsTd

both 02 sensors must be connected and in working order... untill then you will fail emmissions...

bbarbulo

iTrader: (2)

you are not out by much... having functional O2s would go a long way towards getting yourself hooked up with an e-test

punkindrublic

my car has a blown cat and still passed....

SilverCRXSi

BTW you only have one "header", its not plural. Using it in a plural form would mean you have more than 1.

Just a tip. Good luck.

imported_OneBadEk

Does anyone know where I can get cheap o2 censors?? Mine are butchered and I may need 2 new ones. Honda sells them very expensive (like $250 a piece). Crappy tire only sells the front one for $150. Anyone know were I could go??

Please Help!

imported_BoOsTd

solder the old ones... not much can really be worng with them, unless the sensor is shot...

like when you say butchered you mean the wires are cut? if thats the case just solder the wires back together

imported_OneBadEk

Yes, the wires were cut......the problem is, there are four wires on each sensor. A green, white, and two black. I'm not sure which black wire goes where.....on BOTH sensors....AND I'm also not sure if the sensors are shot!! Complications!!!

Also, is there any possible way that my car could pass without the o2 sensors functioning properly?? I didn't fail by much so do you think it's possible??

Thanks for all the help!!

imported_BoOsTd

I doubt it will pass without them... The wires leave the plug in the same pattern as they enter the sensor... so all you have to do is match up the pattern... understand what i mean? you should be able to figure it out, like compare the wires coming out of the plug to the wires entering the sensor.. green to green white to white, then the 2 left over blacks, connect the black beside the white to the black beside the white, then black beside the green to the black beside the green... I dont know how else to explain it...

if the sensors wernt throwing a check engine light before than they should still be good as long as you solder the wires well, and then tape them, or heat shrink them...

johnny23toronto

two options:

1) Make a O2 sensor modulator (a fake signal, google search how to do this, its relatively cheap and easy)
2) use a cheaper single wire sensor (they only cost $90 new). I've heard that you can still use the single wire sensor in the 4 wire sensor sytems, cause three of the wire are for heating the sensor, while there is only one (white or black?) wire that is actually sending a signal.

imported_OneBadEk

Boostzex,

I completely understand what you're saying, the only thing is the pattern is different!!! On the connector, the two black wire are side by side, and then the green and white are side by side. On the actual sensor, one black is beside the white, and the other black is beside the green!!!

Damm!!!!

imported_jaysi

How is this kind of comment going to help him pass?

imported_BoOsTd

Seriously?? damn thats odd...I snipped my wires and soldered in an extension, cuz i went to headder/highflow cat on my dx and the pattern was the same on both ends, was a breeze to wire...

Well you should be using 02 sensors regardless, whether you take the stock manifold off again or not, so I would sudgest haveing that 02 sensor cheat thingy, that tricks the check engine light removed and put back to normal like it should be... then trial and error with the wire connection... it wont hurt anything if you but the 2 wrong wires together, if you get it right then no check engin light, if you get it wrong then CEL and then switch the wires... (just solder the colours, and twist the blacks together untill you know its right, then solder...) thats what I would do anyway...

Then when you want to go back to the headder have a highflow cat installed and the o2 sensors will work with that without giving a CEL

imported_OneBadEk

I'm getting 2 new o2 sensors for my car tomorrow

My question is, how long after I install the new sensors should I do my e-test again. Can I do it right away?? Should I drive it a bit, drive it one day, one week....what's recommended. My sticker renewal is over due and I need to do it ASAP. Do you think it will be okay right after I install the new sensors??

Thanks.

imported_BoOsTd

will work right away... but go for a boot anyway

imported_OneBadEk

Okay so I got 2 brand new NGK oxygen sensors installed on my car this morning. We disconnected the battery, took out the old sensors and installed the new ones. We had a tough time removing the top sensor, so it was heated up with a torch to help loosen it up. We eventually got it out. We put in the new sensors, connected everything properly, reconnected the battery and MY DAMM CHECK ENGINE LIGHT STILL CAME ON!!!

Is this due to some other problem in the car or do you think it's due to the sensors. Before my old o2 sensors got cut up, the CEL never came on.....it only came on after the sensors were cut. Now we installed new sensors and the light remains on!! I'm sooooo frustrated!! We had the battery disconnected for about an hour. Do you think I should have it disconnected for a longer period of time (overnight??). Is there any other way to reset the ECU in my car!! Please help, because I have a feeling my car is going to fail AGAIN because the CEL is on!!

Please help!!:cry:

bbarbulo

iTrader: (2)

you have to wait for the code to reset... starting the car a few times with the fault not present should elimiate the check light... or you can have the code deleted via OBD2 interface. Battery disconnects no longer do isht to clear the memory as I've learned. I use a scan tool connected to a laptop to delete any codes that arise.

imported_OneBadEk

Where can I do to have my car scanned and get the codes erased so I can FINALLY do a re-test!!!

bbarbulo

iTrader: (2)

lordm has the equip't do take care of it... charges are reasonable. PM him