tibbytib

Ok, so I finally choked on my pride, bought some rims and tires for the winter and went down to get my emissions test done. (for those who dont know, they wouldn't test my car because I had 18" rims and 35 profile tires.)

Ok, so, now guess what happens? Thats right, I fail!!

I am failing my NOx readings. My limits are 3.0000 and my reading is 4.8707. Is there any way to reduce these kinds of emissions?

Note:

Just changed my plugs and wires, air filter, oil and oil filter. Car seems to be running great.

I have installed:

Headers
custom exhaust with a cat
airram
spacers
Rside TB
CAI

Just to note, on my exhaust, my second o2 sensor is still in front of the cat (I know, I need to get it moved but too lazy, well, until now!) so I throw a check engine light every once in a while. I had one the day before, so that night I reset the ECU by popping the negative off the bat. Could I have made more NOx emission because the ECU was recalibrating because I reset it the night before???

I know that NOx emissions are most caused from lower cobustion temps and that the cat is either not working or the cat doesnt get hot enough to burn these gases. Would running richer help? How could I do this easily and inexpensively? The EGR is also suppose to help with this. Should I look into replacing it???


Any hints, help, or even brainstorming would be awesome! I got 10 days to get it retested before I have to pay for it again.

HyundaiKitCoupe

if your second 02 sensor is up front than that's what is causing the trouble. your car isn't performing the way it should whether you feel it or not. the two sensors are there for A purpose not two purposes. one reads oxygen output emitted and the other reads oxygen output filtered.

i think that is the problem and only.

Alex01tib

also i suppose it is possible that the NOx levels are abnormally high after resetting the ecu as your car may run a little rich as the ecu tends to do after resetting, but i believe this would only be possible if the cat was on its way out.

They have some fuel additives that you can add to your fuel to help reduce emissions and most of them "guarantee you to pass" where they will reimburse you the price of the inspection if you fail. It couldnt hurt i suppose.

But definatly get that 02sensor moved.

and get the fugg out of CO and go somewhere that isnt super anal about inspections haha.

Ericy321

if it doesnt throw a cel the second o2 sensor should not cause the car to run any different. You could get that additive like alex suggested. Ive heard they work pretty good. And resetting the ecu usually makes it run a bit rich. if anyhting get a scan tool (great to have) and just reset it right before you get there.
wait a minute. it doesnt sound like they do the obd2 check by you? then a nice tuneup and maybe using some additives should work

tibbytib

Thanks guys fing02.gif , Im gonna look into the o2 sensor tomorrow. get me some additives, and try it again. I'll let you all know how it turns out.

Dmitry

And before going on another emission test, drive your car a bit so that ECU recalibrate. Cause if you reset ECU it may produce more emissions before if recalibrates.

hamhead

Just because it doesn't throw a light doesn't mean its not producing higher than normal emisssions, it just may be inside the specs of the ECU but still high, the signal wiring is bad, or whatever. Resetting the battery and then driving to get tested the ECU isn't going to throw a code on the way. It takes at least two cold starts for it to throw a code for emissions if I remember Webteh correctly, thats how it was with my car anyway.

If you have lower combustion temperatures, the plugs/wires might have fixed the problem since they may not have been burning it cleanly. As said, running rich will lower combustion temps as well, which the ECU probably does after a reset.

faithofadragon

i asked a emissions tech here at work this is what he said:

drive your car around for about a hour before the inspection and drive the sh!t out of it
you want the exhuast nice and hot

REDZMAN

Yup.

Go pay the 30 bucks to get a new bung welded in, and get a bung plug for the old one.

Put the sensors in the right place, reset your ECU, then run the HELL out of it for a few hours.

Get that sucker red hot, and go to emissions.

Th3 pa55!!!