griffon

My FD failed emissions twice. The HC (Hydrocarbons) count is to high. The first test it ran 2.3, second test it ran 1.95, needs to be down at 1.2. Any suggestions on what I can do to make it pass? I have 2 weeks to get it to pass.... HELP!!!

NuTbAgSaN

my fd passed...but my other lil bitch...took about a year

1st of all search because obviously this is common.

but, start with spark plugs. thats a big one. make sure the airpump and everything is working, or on my case i had bad cats.

themcneal

iTrader: (1)

You didn't state what your current mods are and that might help people help you.

I know that here in Cali I do the following to pass;

1) Fill the tank with super unleaded (as usual) and add a bottle of one of the "smog pass" solutions from your local parts store (pep boys, autozone, etc.). The bottle I have used successfully has a picture of a Mitsubishi 3000 on the front. The ratio used is one bottle to one full tank

2) After I have run through a full tank like that, I fill the tank 1/4 full with gas and then add "another" full bottle of the smog pass solution, and then head off to my test staion.

I have a downpipe, high flow cat and cat back system.

For me this seems to work, hope this helps,

Mike

adam c

iTrader: (2)

Idle your car to the maximum allowable for the test. Change your oil and spark plugs. Clean is better . Squirt some WD 40 into the intake of your airpump. This will lubricate it if it is "tired".

scotty305

iTrader: (2)

There is a thread in the 3rd Gen FAQ about passing emissions, and also here's another one from the West Coast section.

https://www.rx7club.com/showthread.php?t=454152


Adam, I don't think I've heard anyone mention that WD40 trick. Sounds pretty cool.

-s-

bdennis

This may sound stupid but when I went to the test I had a major exhaust leak. There were so few emissions making it to the tailpipe that I passed. Might be worth a last ditch effort to just loosen up your exhaust flanges and see what happens.

Aeka GSR

iTrader: (4)

you risk drawing in oxegen, which will make you fail the test

bdennis

It worked for me, it might work for him.

juicyjosh

iTrader: (29)

Actually, "drawing in oxygen" is something that will help PASS the test, hence the presence of an airpump under the hood which pumps air into the exhaust....

Oxygen is what you WANT in the cat. It's what binds to carbon monoxide (one O2 molecule) and converts it into carbon dioxide (ie the stuff we exhale when we breathe). Oxygen in the cat also helps the car produce more water vapor (two hydrogens and one oxygen).

Being a somewhat simple device, the air pump is usually in proper working order, and there's no need to spray oil into it. This will actually result in MORE HC's being directly pumped into the exhaust until all the oil finally evaporates. Make sure there are no leaks or cuts in the air pump hoses. It will also help to run a hose from the air pump inlet to an area under or towards the front of the car so it car draw colder (ie denser, ie more) air, albeit just for the test.

*Changing the oxygen sensor should be your FIRST step if this hasn't already been done.* This will help more then changing the oil, which should be your SECOND step, followed by changing the plugs. I passed running four NGK 9 plugs, but using the standard leading 7s and trailing 9s may give you a slightly better combustion at the testing engine speeds. You may also request that the hood open with the shop fan blowing toward the engine, and it helps to test on a cold day (again, denser air). I passed with the GReddy Evo2 exhaust, but replacing your aftermarket exhaust with the stock, more restrictive one will cause the gases to marinade longer in the cat, and help the reaction process slightly. This will help by the smallest of margins, but sometimes you pass by the smallest of margins.


***We want to make sure we know what we're talking about here before posting certain "advice" on any forum....***


We should all be trying to help each other out, and only post legitimate information versus untested hearsay. These are our cars. If someone doesn't know what it's like worrying about your car passing, it's an uneasy feeling of uncertainty and worst-case scenarios, and we've all got better things to think about. I'm trying to help you pass based on the fact that I've done it.

Over the last two years I've legally passed two FDs on the California dyno load test, which is the toughest (and somewhat ridiculous) in the nation, so there is a certain credibility to the information above. I'm also a med student so general chemistry, organic chemistry (chemistry of carbon) and physics may sneak it's way into my posts.

Good luck with the testing.

Josh

93 FD Touring
Apexi Power FC
et cetera

griffon

Im Dying here. I have swaped plugs, changed oil, added the Smog Pass crap to my gas, and after failing again I checked my CAT and its in proper working order. So what do I do from here???? I keep seeing people list change the AFR to about 14.7, how exactly do i change the air to fuel ratio??? Still needing help!!

Heres a list of known mods :
RB Down Pipe, Mid Pipe and Exhaust (interchangable cat or straight pipe)
Apexi Dual Power Intake
Ported Waste Gate
Koyo Radiator
Aluminum AST
Pettite ECU
Greddy SMIC
Greddy Profec B spec II

Could this also be the reason Im failing????

griffon

(read posting #10 as well please)
I failed with both the stock ecu and the Pettit ecu. I actually got better numbers with the Pettit ecu. HC 2.7 on stock, 1.95 on Pettit ecu. Also testing my car it is running very rich, cat is runing at 230 degrees before the cat, then rises to nearly 750 degrees exiting the cat. Also showing that the cat is working over time with to much unburnt fuel to convert. Hope that helps you help me....

adam c

iTrader: (2)

Are you failing at idle, or at higher rpm test?

rynberg

Try to borrow a stock cat from someone in your area for the test. Your car must be FULLY warmed up -- go and get on it for a while before pulling into the smog place.

If you think your cat and air pump are both good, and you have new plugs, etc., something to check would be that the ACV is working properly and is actually directing air toward the cat. Speaking of which, you DO actually have the air tube hooked up to the cat for testing, right?

I passed Cali dyno smog tests last fall with only 200 miles on a new motor....

*streetported
*intake
*Bonez hi-flow cat
*cleaned primary injectors, bored out secondaries
*Cosmo fuel pump
*9 plugs all around
*SMIC
*Power FC

fdeeznutz

That is what happened to me. I failed 10 times before I realized the the ACV wasn't working.
Just unhook pipe to cat and feel if any air is coming out.

griffon

The car has been fully warmed up (and why would I borrow a cat when mine works?), but I will check to see if the ACV is working....

FDNena

iTrader: (2)

I was having the same exact problem this summer. I tried everything and couldn't figure it out. Took it in with the stock cat. I don't take my car out much since when I do it is to pretty specific destinations so I ran the car pretty hard for about 40 minutes before taking it to the test again. I kept the RPM's as high as I could from the highway to the test sight. It finally passed.

Good luck I know how frustrating it can be!

Mr rx-7 tt

iTrader: (5)

Your cat may be working but it's your problem. Change it out.

griffon

Just out of curiousity how is it my cat if its working? The car never has the cat on it, it has a full exhaust system on it with interchangable straight pipe or the cat? So why if my cat is working is my cat the problem?

adam c

iTrader: (2)

Look!!!! Someone trying to help you has asked a question that you have not answered. Very Rude!!!

21K95RX7

how do you like that cosmo fuel pump? is it better than the supra pump?

griffon

Sorry, I believe I am failing at the higher RPMs. Like I said the Hydro Carbons are at 1.95 supposed to be at 1.2 so Im not failing by much but Im still failing.

Angel Guard Racing Team

Can you please post all of the passing ranges? I just need an idea...

Rmagic13b

well could u try to put on the stock dp? cuz that would be another cat on there and ur not failing by much so it would seem like dat would help do the trick.

danny hahn

Is the clutch on the airpump engaging?

griffon

I dont have the stock dp so that very well may be it if I could borrow one from someone. I dont even know if the airpump is hooked up on my FD3, where is it located and how can I check it?