whlimi

iTrader: (11)

Hey guys,

I got my emissions test done last night and I passed everything with flying colors except for NOx. Limit was 450 and I got 750. Here's the thing though, my cat went about 2 months ago and I was running a straight pipe and I just got a used cat from a buddy of mine ( cat works fine). I had it installed and went and got emissions done about an hour after installation. Is this why I failed? Should I have waited a bit longer or do I have other issues? I didnt fail the NOx badly. Any suggestions?

Thanks in advance.

99BlackMaxMS

iTrader: (85)

I am assuming that you have a y-pipe as well and have gutted the pre-cats by doing so. If your car hadn't been running for 30+ mins, it could very well be the case. When you go back, try driving around for an hour or so and then going to get it done.

whlimi

iTrader: (11)

Thanks for the advice. Anyone know if over the counter additives might help slightly?

mmg23max

yes there is you can go to Auto Strauss and ask them for Fuelon Power additives

whlimi

iTrader: (11)

I had the car retested and failed NOx again. Everything else is amazingly low. I'm beginning to think that I many have an EGR problem. I tried searching for some EGR threads but came up with nothing. Are there any links that provide information on how to clean the EGR valve on a 99. I found links for 95-98 but 99s are different.

chillin014

iTrader: (67)

ooh EGR thats a fun adventure...to see if its opening you can reach your hand under the valve and feel if its lifting up while revving the car. its kind of hard to explain.

whlimi

iTrader: (11)

Is it hard to get a sense of when its opening when you're feeling it with your hand? There are vibrations from the engine and its kinda hard to try and figure out if the valve is opening or not. I'm planning on taking it out this weekend and having a look at it. Is there anyway I can test its functionality once it's pulled out?

Bobo

My NOx reading was high when I went through emissions testing a few weeks ago, but I passed. It was about the same 2 years ago when I went through and a year ago I threw a code for an EGR control solenoid and replaced it.

I have a Budget y-pipe and I don't believe I ran the car long enough on a cool day before being tested this most recent go around.

Next time I will go through after a good highway run and not sit in line up for 10 minutes idling like I did this time.

njmaxseltd

iTrader: (19)

How old are your spark plugs?
When was the last time you cleaned the TB?
Is your air filter dirty?

You might have a lazy o2 sensor.

whlimi

iTrader: (11)

Anyone know how to loosen the flange nut that holds the EGR valve. This is the huge bolt that is between the EGR and the exhaust pipe. Is it normal or reverse threaded? Any help is appreciated.

whlimi

iTrader: (11)

The plugs are fairly new and the TB was cleaned roughly 30k KMs ago so it shouldnt be too dirty. I dont have any codes for O2 sensor but maybe I will replace them. Seems easier than trying to replace the EGR valve.

chillin014

iTrader: (67)

i think its normal..i had to go down to the hardware store and buy a HUGE (like 2 foot long) wrench wrench to break it loose. i cant remember the size of the nut I think 30 something..i'd haveto go check

whlimi

iTrader: (11)

Thanks for the quick reply. I will have to do the same.
Much appreciated.

KRRZ350

iTrader: (29)

Remove just the upper tube first, that's where they like to clog, right were it goes into the manifold. This requires bending a pipe that gets in the way of fully removing 1 of the nuts from the stud by the coolant log, or cutting the very end of the stud with a dremel, but yopu should be able to get access to the back of the intake manifold hole where they clog even if you leave that nut 1/2 on, you'll see what I mean

Manual lifting up the egr @ idle will tell you if it is opening-the engine should stall or come close to doing so. Or you can hook up a vacuum pump (speed-bleader for brakes) and manually apply vacuum to it.

whlimi

iTrader: (11)

I just pulled a code. 0107
Cant find what it means anywhere. This is really starting to annoy me now. Wish I could cheat emissions somehow.

S1cTech

i pulled a 1402 EGR code... possible temp sensor could be an issue too ot clog in orifice... all i get is the SES light... and prob bad gas mileage... I never really got a chance to look at it... but nissan wants like $400 to look at and do the work excluding parts....

so im gonna do it wen it gets a bit warm out...

whlimi

iTrader: (11)

Anyone ever get code 0107 before. I'm sure I read it right ( 1 long flash, 7 short flashes). I cant even clear it. If anyone knows what this code means please help me out. Thanks.

aussie983

iTrader: (16)

Funny thing, cuz I had the same problem. Passed smog fine 2 years ago, put on a y-pipe about a year ago. Made sure i had it warmed up for at least half an hour before smog check, but i got double the NOx limit, but passed everything else with flying colors. I put on the stock pipe, gave it about a week to adapt, but even then I passed, but NOx was still marginal. Still puzzles me why i have such high NOx... I also have no codes :\

bluejays026

i had to put my cat back in and run it for atleast 500 miles before my car passed the test.