m00njal

Just failed smog test today... =(

Apparently in the 15mph (first phase I assume) part my NOx emissions were double the limit, and in the second part, passed, but pretty damn close.


Thurznite just recently helped me replace a knock sensor, and currently I have no other codes. My only mod is a y-pipe (warp speed).


The technician said it could be EGR and/or timing related, just off hand. I understand that I need a proper diagnosis, but any ideas as to where I might want to start? I don't even know what EGR stands for.....and know very little about it. All advice is appreciated.

I'll scan and post my smog test later tonight .... (pst)

98 SE with 179600 on odo, y-pipe is only mod.


EDIT: I know I posted this thread in two different sections, a local member told me to post here to get some better feedback -thanks

m00njal

Update: Scans of smog results

SNOMAX

iTrader: (14)

Judging by your NOx levels, it looks like a blocked or non-functioning EGR. I suggest cleaning the guide tube first. If that's heavily or fully blocked--that would do it. Otherwise you may need to put a multimeter on your sensors and make sure they are in spec. But it's pretty much EGR.

m00njal

Alright, sounds good. I just don't know the exactly order of what to check first.....the EGR check valve? guide tube? or the EGR-C solenoid ? I'm searching right now for an overall how-to on EGR checking/cleaning.

Any links would be handy

m00njal

I researched the EGR system now into a lot of detail from the FSM, and it just bothers me that though I don't mind checking it, almost all the diagnosis pointed out in there starts with a DTC engine code, while I have none.


Should I be looking into other things? air filter? Intake leaks? EVAP system?


Also, after searching I've seen posts that claim there are "millions of EGR threads" and "many links and how-tos" but I don't see anything in drastic detail.

Lastly, when performing the smog check, the technicians said my engine was running very hot to pass NOx emissions, and asked if my coolant was low. I'm sure it isn't, because of a recent front-end accident I replaced my radiator and replaced the coolant in the system. However, while my TEMP gauge is normal, under the hood it does feel like my engine is significantly hotter, and also Thurznite noticed this, and we both also realized that the crappy aftermarket chinese radiator I bought ($55 FTL/FTW) is like a 1/3 thinner than the OEM radiator.

Could my engine be running excessively hot, with only minor EGR problems, and maybe I should be addressing my cooling? I will take pictures soon and upload of the radiator.

vilmaxima

Also with the warpspeed y pipe, you have to let it warm up pretty good before getting the test done, or you will fail it. Drive on the highway for about half an hour, or somewhere where you can get it hot, then try the test again. As for the EGR, it might be that the tube is clogged and the sensor is not reading as it should. Fairly easy to take off and clean. You can find threads on how to do this. Hope that helps.

nadir_s

^^ yes, make sure your car is was running for a while and HOT ... hell, when I ran mine and failed, all I did was run some fuel cleaner and then ran the car on the freeway for a bit. Then, while waiting for the smog, I let it just idle to keep it running.

It passed w/o a prob then.

tack86

iTrader: (3)

He knows the engine has to be warm for the use of the ypipe, that's common sense. And from the post it was warm, the issue has something to do with EGR of some sort. ypipe is not the issue here, however I still think he's going to swap the stock one back one for simplicity sake.


can any experts chime in on this? weather its his cooling, egr, or both?

Mrbizness1

just curious, they still check smog separately in Ca? In NY they hook up to the OBD system, no codes and you pass.

tack86

iTrader: (3)

yes they do, they first check for codes with OBD system , then they do the testing at 15mph and 25mph i think

MOHFpro90

iTrader: (11)

Who got banned and is trying to exact revenge?

I could take a couple of guesses...

m00njal

Wait, what? I'm confused.

tEh_mAx

Do you have to have this checked yearly?

SVI30

No smog is only checked once every other year. In some year it is checked on a dynamo at stations called Test Only Station.

To OP,
What is the different between socal smog and Calif smog? Can your car pass Calif smog? Just joking.

The Wizard

iTrader: (43)

This is the worst thing he can do when his NOx levels are as high as they are. Having your car HOT is great when the EGR system etc is functioning properly, but in his case, he wants his engine as cold as possible to bring the NOx readings down.

When I smogged my girlfriend's Ford Probe, it failed (brought it in nice and HOT like I've always heard to do). After doing lots of internet research, and talking to many mechanics, I learned tons about how to correct for high NOx readings. Even the smog shop said next time they'll let my car sit for a couple of hours before running it and let it cool down as much as possible. I added a whole thing of water wetter to the system as well. Passed the second time.

I'll add more later when I have a chance. Learned a bunch about what the culprits for high NOx can be and what I did to get the Probe to pass.

tEh_mAx

The Wizard -

Nice tint. What % is it?

brandonS

I'm having a similar problem. I failed smog twice now, the first time I had NOx output of around 500 at 15mph and then I had 625 on my second fail.

I changed out the sparkplugs, pcv, fuel filter, air filter, and had done an oil change not too long ago. Then as suggested on these boards I started with the EGR pipe, it did not have a clog, I cleaned what grime was in there with some carb cleaner and put the pipe back on. (all of this was done before my second smog)

Not sure what to do next, some people say clean the EGR valve but since the pipe wasn't clogged would the valve still be the problem.

I have also read that the catalytic converter may be the problem and I only purchased the car a little over a year ago and it was never mentioned wether or not it was changed out before.

Any ideas?

allensteiner21

iTrader: (6)

move to a state without emissions laws - MT FTMFW

that's the only idea i have right now though

choray911

iTrader: (1)

Dats why I moved out of Chattanooga, TN to a po dunk town in north GA.

96blackmaxSE

iTrader: (30)

word up, no emissions testing in KY...I'd be completely screwed

Mrbizness1

Emissions testing is a federal law, soon all sates will do it or lose federal funds. Its the big government everyone seems to want.

allensteiner21

iTrader: (6)

MT already refused the federal ID plan even though the feds threatened with budget cuts. too many gun owners up here to be affraid of what the administration says
plus too many people in poorer states would all of a sudden loose the priviledge of private transportation.

Mrbizness1

Many people in my state, NY are already driving around with expired inspection stickers because many of the repairs are to costly for the owners and are for older vehicles which aren't worth the cost. You have to spend nearly $500.00 to get the car fixed and if the light is still on you get a 1 year exemption. This year they started enforcing a law that the DMV will not let you renew your registration if your vehicles inspection is not up to date.
Imagine what will happen when they start controlling your health care.

maxgtr2000

iTrader: (29)

That's the hope and change clowns voted for. Some of us knew better. It will eventually get to every state unless they seperate from the union. Eventually if your vehicle doesn't get 30+ mpg it will be deemed illegal. I was wondering why people are turboing smart cars now. To the OP google high nox and see what results come up, I was going to say change your oil but you already did that. I would go take the test with it freshly changed and new plugs.