Failed Inspection. Poop.

[Shift__BODOM]

took my long ovedue nissan 240sx KA24DE for inspection, only to fail.

New: O2 sensor, Catalytic converter (2 months old), plugs w/o signs of oil

Results: Low Speed (15 MPH)HC(PPM) Standard: 136; Reading: 226CO(%) Standard: 0.76; Reading: 2.68CO2(%) Standard: N/A; Reading: 13.3O2(%) Standard: N/A; Reading: 0.5NOx(PPM) Standard: 1045; Reading: 2106DILUTION(%) Standard: >6; Reading 16.0

Results: High Speed (25 MPH)HC(PPM) Standard: 132; Reading: 214CO(%) Standard: 0.73; Reading: 3.32 (lol)CO2(%) Standard: N/A; Reading: 12.9O2(%) Standard: N/A; Reading: 0.4NOx(PPM) Standard: 945; Reading: 1674DILUTION(%) Standard: >6; 16.2

Ran codes, got a 55 as always. im thinking EGR or PCV. The hose that connects the AIV to the intake is off with a big breather filter on the end of the intake bung. the AIV is exposed to unfiltered air. i dont know if this will do anything.

help! i have 15 days from today to get it repaired and i need any help i can get! thanks all!

[navysnail]

looks like you need a tune up, its running a little rich and posibly the egr is not functioning correctly like it should

[180fan]

Check the EGR for those high NOx figures. Have you checked your timing? Put your stock airbox back in and reconnect your aiv hose. Another thing to check, the vac lines to your EGR, the one in particular, the one that runs from under the bpt to the egr. Good luck.

[Shift__BODOM]

im pretty sure i know how to check the EGR, if its bad, do i need to buy a new one? he said to check the fuel lines and the spark, i have new bosch platinum +4's and accel 300+ thundersport or something like wires, so i know my spark is powerful enough. i dont understand what he means by fuel lines however. does he mean the fuel injectors? like to check if they're clogged, or the actual fuel lines? i run 93 octane all the time. do i need a new fuel filter??

[s13sr20chris]

problem number one is the bosch plugsput in some ngk plugs. that alone will get you closersometimes you can fix egr just by removing the valve and cleaning it out with carb cleaner. also, the bpt hose is a major culprit.

you are running rich. check maf voltage, coolant temp sensor and harness, and do the basics like fuel pressure, ign timing, etc.

[Shift__BODOM]

any preference NGK plugs? i dont know if there are any others, cause all i know about are NGK platinums. about how much will a set run me? about what specific (or at least close) plug type id need, i have intake, exhaust, pulley, performance radiator (does nothing for emissions...or does it?) and of course plug wires.

anyway, inside the EGR, will there be some like, crud stuff or will it just be black? what am i looking for to decide whether or not its "dirty" or just generally f*cked? i know it'd be a good idea to clean it anyway, but i want to know what exactly made me fail. im gonna take the advice about the stock airbox and connected AIV. when i installed intake, my car stopped idling, it would just die, and my dad took it to a mechanic while i was on a trip and said that the mech turned some screw on the throttly body (bad) and the idle was still WAY too high, like 1200 w/o ac, so i turned it down via the idle adjustment screw to about 750-800 (good). pretty much ever since then, its been blowing white smoke after it's been idling for about 5 minutes. in fact, when they were doing the low speed emissions testing, there was a plume of white smoke behind my car for about 15 seconds from continuous white-smoke-blowing-out-of-tailpipe action. i also have a bad rattle right below my valve cover about where my timing chain would be...are my tensioners f'ed? also, i think my oil pan is leaking cause the gasket is shot...? will all this cause it to fail?

[180fan]

EGR will be coated black with soot. Carb cleaner should make pretty good work of it, might have to stab at the big chuncks with a small screwdriver, but it'll go. Clean it, replace the vac lines.

NGK's, if you use the regulars, they're a buck something at my local Kragens, no need for fancy stuff if you're trying to pass smog. Just make em fresh and that'll be good. Lightened pulleys shouldn't effect your smog.

EGR test = with car running, push up on the diaphram of the egr, if it stumbles, you're fine. If not you're screwed.

[Shift__BODOM]

awesome, i did the EGR today, found out that the vaccum line from the BPT to the EGR was screwed. completely torn in half, nothing was getting to the intake. anyway, i instantly removed the hood when i found out how to solve the problem, otherwise, id get too claustraphobic and probably die or something. yeah, i cleaned it out thoroughly with carb cleaner, replaced that vaccum line, and finished up. took me like an hour and a half minus hood removal and re-installation...damn thing wouldnt line up right...oh well, ill be checking voltages and such on monday, since im booked for tomorrow, i can't even recharge my air filter. damn. im going to see if i have enough of my stock airbox to reinstall it.

should this be enough to cause me to pass? could that one vaccum line and the aiv not being hooked up really cause me to fail like that? the numbers seem really high to me. maybe plugs will give a better combustion. also, should i run the usual premium 93 octane for the inspection or just regular 89 octane? does it make a difference? should i do a seafoam runthrough? could an oil leak adversely affect emissions?

damn, i just realized how many questions i just asked. oh well, wont know unless i ask.

[s13sr20chris]

good, you should be closer now. oil leak is nothing, regular gas should be fine(although a little denatured alcohol will help), and you prob have another issue. you prob have a fuel control issue like maf or something. a fresh cat could not hurt either.

[Shift__BODOM]

the cat is less than 2 months old, so i have a feeling its not the problem, i replaced it after i did a seafoam, and ended up replacing my whole exhaust from the cat back with a custom 2.25" setup w/magnaflow muffler. should i put the silencer in on my muffler, or will it make a difference? ive been searching the FSM for how i can test the MAF voltage and what readings are appropriate and have come up with nothing. any help with that? other than that, i dont know of anything that would be messed up except for the fact that my rings might be a little overworn. is it true about the denatured alcohol? ive heard the same from someone else one time, probably in another topic. if itll help, where can i get it, and how much should i put in? also, since there is a little white smoke, im going to add some "smoke away" oil additive tomorrow. im going to go back this week probably around wednesday to get it retested after i get all the stuff taken care of.

oh, before i forget, should i reset my ECU/pull some fuses and make the ECU relearn everything by driving VERY conservatively? i usually am on it pretty hard during acceleration. does driving hard cause the ECU to adjust the fuel map, making it run really rich?

so many questions! thank you all for helping me, especially you chris and 180fan thanks a lot you guys, it means a lot for you to listen to my overabundance of questions and come back with just as many answers.
Modified by Shift__BODOM at 3:34 AM 1/17/2005

[180fan]

a catback can hurt your emissions. If you've something like a 3" exhaust, it can significantly lower the backpressure needed to open the EGR. I had major difficulties with my emissions from my catbacks. Th 2.25" shouldn't have as much effect on your emissions as a 3" but very possibly still do harm to your emissions. Try to find a local guy with a stock muffler, or get a cheap one like the previous owner of my car, who got a $23 muffler (yes, $23 installed).

The denatured alcohol helps with emissions but can mess up your motor if you decide to drive in a sassy manner.

Your richness of mixture can also be related to your coolant temp sensor. The mafs, you should use a small needle and poke through until you get to the wire inside. Then check it, take care not to short the MAFS wires though, then measure with a multimeter.

Another good idea is to check the resistances across the ignition wires if you've already got the multimeter out. I forget the amount of resistance they're supposed to have across them, but they're in the FSM.

Have you also checked your timing?

[Shift__BODOM]

well, its 2 1/4" so the bacjkpressure is pretty close to stock, and with the silencer, which just makes the muffler opening a lot smaller, the backpressure should be pretty close to stock. theoretically speaking though. id go witht he idea of poutting the stock back on, if my cat wasnt welded to the pipe coming from the engine and the catback. custom = welded.

ill check voltages tomorrow. thanks for the help all