Hey i need help with smogging my 94 civic ex d16z6

only mods are hi flo cat with greddy evo catback

here were my results

15mph
HC - 92 (max 169)
NOX-1100 (max 700)


25mph
HC - 57 (max 63)
NOX-130 (max 700)


i think i can pass the NOX if the guy woulda warmed up my cat a bit more, i didnt drive it for too long before smogging whuich i shoulda done since i passed the 2nd run. but my HC sucks. today i checked my plugs and im runnin 1 step colder plugs...do u guys think thats the problem?? I changed to stock plugs too and added some guaranteed to pass stuff. i really need it to pass smog because i leave back to the air force in 3 days i gotta get this done any help is appreciated!

 

I had the same problem, but I switched out my spark plugs, spark plug wires, and distributor cap for back up! It passed with flying colors! Just double check your spark plugs and spark plug wires!

 

revert to the stock recommended spark plugs. what is wrong with your HC numbers? they are under the limit. your NOX number are usually high from a cat that is not functioning properly or is not efficient.

 

Looks like your catalytic is not at optimal efficiency. Try running the car hard for 15-20 minutes, then smog it. Try using OEM plugs. Your car, as you described it, sounds stock and shouldn't have any problems with passing. Good luck!

 

i believe your hi flo cat is the culprit.

 

Wait a second! The high flow won't make it fail by itself, sounds like theres some uncombusted fuel, some fat injectors, a high duration cam or a chipped ECU. Combine any two with a high flow catalytic, then I can believe it's not passing. I can easily pass you're car with all the above, megasquirt and a turbo and still be below allowable limits. Sounds like someone is taking you for a ride.

Below is the system I use to tune for best emissions. Running a complete Megasquirt with a Standalone ECU will render the best results.

http://www.megasquirt.info/index.html

 

NOX is directly related to cylinder temperatures(actually combustion temps). make sure your timing is correct.

 

ok i passed NOX fine. the plugs are back to stock and timing is 15. i ran the car hard for 20 min. i also ran a tank full of the guaranteed to pass crap, but i ****** failed HC. the max was 60 and i got like 70. expletive this **** and expletive smog laws

 

I failed my NOX test miserably last time I got my car smogged and this is what we did at the shop.

-Turn the car on
-stick something in between the throttle cable so the butterfly on the throttle body is open a little
-get a spray bottle of water
-spray a mist of water into the throttle body every 15-20 seconds (do that until half the bottle is empty)
-drive the car around for a few days to get rid of the code
-get it smogged again and it should clean some of the buildup on top of the cylinder heads and reduce the temperatue a ton.

Im not saying this will positively work for you, but it brough down my NOX DRAMATICALLY! Im talking several hundred.

Good luck

 

whoops, just read your post that you passed NOX - sorry

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by vg7z &raquo;</TD></TR><TR><TD CLASS="quote">ok i passed NOX fine. the plugs are back to stock and timing is 15. i ran the car hard for 20 min. i also ran a tank full of the guaranteed to pass crap, but i ****** failed HC. the max was 60 and i got like 70. expletive this **** and expletive smog laws </TD></TR></TABLE>

Your highflow cat could likely be the source of your problem. You might be able to find a used stock cat for cheap around here. I bought a stock gsr cat for like 40 dollars on ht. I hope you get it figured out

 

high HC is unburnt fuel. check the condition of your oxygen sensor by measuring its output voltage. if it is sluggish to respond when it is at operating temperature or is very low all the time... that is your most likely problem because the car is thinking its lean, but is actually rich.

 

Like i said before, its your cat. The 02 might be affected also, so change out both and you'll be set. I had the same problem with my car, i kept failing HC's so i changed out the 02 sensor first, but still failed, so i changed out cats and finally passed. My stock cat looked perfectly fine but was actually dead. hope that helps.

 

switch everything out for stock you can emissions wise. then just switch it back after passing!

 

so i guess that "guarenteed to pass crap" didnt work.

 

Hydrocarbons are the component of fuels that produce energy. HC emissions from a vehicle are basically unburned fuel. High levels of HC emissions indicate incomplete fuel combustion, either the result of a misfire or of low engine compression. It pretty much as nothing to do with the catalytic coverter because that is suppose to filter the CO levels, but it appears you have a problem with sparks if im correct. So did you make sure the spark plugs are gapped correctly, new spark plugs wires would be great and make sure they sit real tight, and switch out your distributor cap if possible? I can almost guarantee you'll pass by a hair, but you'll pass!

 

https://honda-tech.com/zerothread?id=1482489

 

Post your results, so we can figure out what the exact problem is.

 

As a X State inspector a high flow cat doesn't always let you pass the emissions test. Run it a little lean and you should be alright. Good Luck

 

I agree with "Pedal 2D metal"... if you run it lean and run the rollers on a hot cat, you'll be alright. Please double-check vacuum hoses, O2 sensor, and maintenance records to troubleshoot your problem.