Well I thought i was going to pass again but it looks like i failed. Out of the 5 things that were wrong last time, 4 have been fixed and 1 is left, the dreaded HC's, heres what i had on my old thread:

"I failed smog heres what I failed:

HC:
MAX MEASURED
15 MPH 121 556
25 MPH 96 395

NO:
MAX MEASURED
15 MPH 807 907
25 MPH 746 765

They also said my idle needed to be lower and my air box put back to the stocker uncut box.
I also Failed the ignition timing check due to the rpm.."

Well i've set timing to factory specs, tps, new fuel filter/fuel lines, every single vacuum line changed, k&n oem drop in filter, injectors rebuilt, ss omp lines, 02 sensor and some other minor things. But I still failed and heres what the reading was:

HC:
MAX MEASURED
15MPH 121 560
25MPH 96 400

So now its either "pass it" or pass it by doing some tricks. So far with the help of dDub i've put the airpump to pump air into the split air pipe, and the car runs just as same and normal with it doing that, should that bring down the hc's alot? Could i retard my timing? I have also been in a dilema whether to buy a SAFC II or buy a rb header/presilencer (only 300!) and finish my rb setup, if were to buy the safc II could i make my hc's go down and pass it? S4 NA bone stock btw. Thanks

-Andrew

 

The only tip/trick I can give you is to find someone who will do it illegally. There are several places you can go to and just ask. Many will turn you down but when you find one it usually only runs $150. I know its wrong and all, but it could buy you some time to get the car fixed instead of dumping all that cash, you have 2 years to fix it.

 

^Thanks alot for the suggestion, but thinking about it, 150, yeah thats a nice chunk of change, why not drop in one more hundred and buy a afcII and tune that sucker, ddub came down almost 2000 HC's by some tuning with the afc and putting back on a cat and he passed smog. I really want it smogged by this week cause i'm going to be out of state for the next week.

 

Yea, 150 is a bit. Since your car is bone stock its probably not worth it. I have all emissions removed and full RB exhaust (no cats) so 150 is alot better than putting all that back on.

 

First of all. How old is the main cat? From your readings it looks like the cat is not doing it's job. Remember these are the dirtiest running engines there are.
2nd) Have you checked the operation of the acv system. Is there air getting to the cat. Also check to make sure the air is not coming back thru the exhaust check valve. If it does then it will raise the Hc's.
Are you sure you have good spark from the coil packs. possible have small missfire which will cause it to go lean and raise the Hc's also.
do you hav anyone in your area that has a Afg that you can tie into your O'2 for
readings?.
the afm also may be out of adjustment and can be recalibrated. the only problem
is you need a Gas analyzer or AFG installed to see where it is going.
my recommendations are as follows.
1). Have cat checked at local muffler shop. outlet temp should be much higher than
inlet temp. Most shops check them for free.
2). Make sure the acv valve is working and inducing air into the cat.
3) make sure that the exhaust check valve is not leaking back into the intake tract.
4). Borrow a friends car that is the same make and year, swap id plates and cove the Vin on the dash with a dashmat so it can't be moved. Swap paltes over and have it smogged. Did i just say to do something illegal. As they say in congress.
" I have no knwledge of that sir". If only you guys were closer to me instead
of me being halfway between SF and LA i couldmake more money, i mean help you out, lol. rx7doctor

 

110k miles on the cat, just like the rest of the car

what check valve are we talking about, the one that goes onto the lim and the acv goes over it? thats good and i did test it by blowing thru both sides. I do have good spark, that was checked not to long ago. by afg do you mean air/fuel guage? i can always buy one if thats what you mean.

1. If this method i have right now fails, i'll have that checked
2. acv is working, and is putting air into cat
3. exhaust check valve, thats for the acv right?
4. thats to long LOL

Thanks for the help man! btw whats your opinion on the safc II?

-Andrew

 

Approx 90% of the time our cars fail because the cat is worn out. remember that
their is an extreme amount of heat going thru our exhaust and our fuel in Ca pretty much sucks.
As far as the Exhaust check valve. It is the valve that goes down the pipe to the
cat to induce air. If you take the pipe off at the back of the lim and air comes back thru the valve is bad.
I'd say by the mileage have the cat checked first before anything.
Guys have also used a portion of alchohol in their fuel to pass emmisions. But personally i have never had to do anything besides either putting on a new cat to replace the old worn out 200lb monstrosity. or having to do alittle fine tuning.
Yes AFG= Air fuel gauge.
Pretty good investment when fine tuning.
The autometer one is far less expensive than KN. All you do is tap into your existing o'2 sensor and hook up a few wires.
rx7doctor

 

Most of the air from the airpump goes to the air control valve........then thru the checkvalve (round disk b/t the acv and intake manifold), into the intake manifold.....then if its a 86-88 non turbo, goes to a square passage at the front housing and the rear housing (NOT front and rear ROTOR housing, but front and rear housing) where upon the air goes straight down those housings to the bottom where it exits a somewhat triangular passage and enters the ROTOR housings at the right bottom of them and goes into the exaust ports. That's why it's called PORT AIR. That is where MOST of the air from the acv goes, especially at idle and low rpms i.e. below 3400/3600 rpm.

Over that speed the Relief Solenoid closes vacuum from going to the Relief diaphram in the acv and allows most of the air to dump overboard into the silencer in the right front fender.

If I were you, I'd pull the large hose off the bottom of the acv (it runs fwd to the right front fender's silencer). With the engine FULLY HOT, you should not feel more than a whisp of air coming out the port where that large hose was connected. Now rev the engnine over 3800 rpm. The air should pour out big time while over 3800 rpm.

IF air is being dumped all the time into the silencer, then you are either missing the vacuum from the relief solenoid to the acv or the relief diaphram in the acv is busted.

One reason you might be missing the vacuum from the Relief solenoid, on a 856-87 version, is because the water temp switch at the bottom left of the radiator is not connected. That switch will effect the Relief Solenoid. If the water temp switch is busted, then take those two bullet connectors that go to it, and couple them together to make that circuit without the switch being in the circuit. Now the Relief Soleniod should work and allow vacuum to the relief diaphram inside the acv.

Or try this with a fully HOT engine. With the engine idling and fully HOT, remove one at a time, the two vacuum hose just above the acv. There should be vacuum on each one at idle. If not, find out why not.

OR try this. Those two vacuum hose above the acv.........with the engine OFF, attach a spare piece of vacuum hose to one nipple at a time and suck. The diaphrams if good will hold a vacuum. If not, the acv is busted internally. The Switching diaphram MUST work or else there will be no passage for the airpump air to get to the PORT AIR i.e. the EXAUST PORTS AT THE ENGINE BLOCK.

Turbo ACV work differently. They use PRESSURE to operate the RELIEF diaphram and vacuum for the Switching diaphram.

I passed emissions on my 87turbo this day. The HC were 20 something range. I'm allowed 125 I think.

There's a very nice schematic of the ACV in the online FSM. Page 4A-38

 

If i am not wrong 87 gas would pass smog easier than 91. Here is why i think so.... If the gas was to burn slower wont that give you a higher HC reading? Also would it be a waste of $ to put a AFG on a stock O2? I mean the only O2 reads from .1 to .9 acurratly. I am not trying to say any thing but these are some things i thought about when i was reading your thread.

 

Stupid question.... But was the car hot when you brought it in for the smog?

 

Once the catalyst is hot, it's usually working fine enough, plus most emissions places have you in line for a damn hour..

 

And it's probably NOT the 02 sensor because you failed at IDLE (where the 02 sensor is NOT in the loop), as well as 25mph (where the 02 is in the loop)

 

Hailers, large hose at bottom of acv, one going to airpump right? i "blocked" it off because i rerouted the air pump to push air into the split air valve, if i "unblock" it could i still do the test, and the test for the vacuum, when i suck up should i be pulling in air or nothing at all for it to be working properly

twisted driver, yes the car was at operating temp, i went home and i hit the tach at 4k for about 1 minute, drove to the place (bout 30 seconds away) and was tehre for about 10 minutes waiting, told the guy to rev the car, probably had the car at 3k for a bit less than a minute


impreza2rx7, no one was there i was smogged immediately

Lotsa good help and good info thanks guys

Edit- any of you guys have opinions on a safc II to make me pass?

 

You could take a safc and dial out say five percent b/t the lowest setting and say 2500 rpm. It might help. I doubt it'll correct the whole problem. I could be wrong though.

You already have a variable resistor you can turn to L. How far? Depends. As long as the engine will still idle and stay idling. It's only good for idle though. Not the 25mph speed.

I always pull up to the station and leave the car idling til they get to it.

 

I ran into similar problems with almost all of my cars I have bought used. Slap a new main cat on there and you will be 99% of the way there. Make sure to keep you're old cat, this way you can save you're new one, swap the old one back on there after you make make it more free flowing.

Keep the new cat when the smog man wants to sniff you're pipe one more time... It works well as long as you are up for a little effort.

 

Thanks for the help guys, yet another question, I've read several times that cats that are sold at local shops "hi-flow" will not live against the power of the rotary, but i'll only use it for smog purposes if i were to purchase one with welded flanges to put it back in for smog time, because if i buy the rb header/presilencer i would run a full setup and no need for cats for 2 years. So quick and simple, if i buy a generic hi flow cat will atleast hold up for smog times? i don't want to keep spending damn money on this crap i want more mods!
btw i have my smog certificate around but if anyone in cali can correct me on this, they don't measure idle for smog do they?

-Andrew

 

Yes they check base idle, and run it on a smog dyno. So you will need to make sure you're idle is within spec otherwise you will fail.

In my experiences doing the same thing a cheap cat will be fine for swapping on and off for smog times. No worries there.

Enjoy the car and flames without that cat though.

 

http://www.expresswayconverters.com/...id=220&cat=RX7

http://www.all-catalytic-converters....converter.html

Theres 2 stores with cats, which one do i need, they look like they're ready to bolt up, precats aren't needed correct just the main cat? I've heard precats aren't really needed. btw i'll definetly be shooting flames, running a full rb exhaust! Thanks

-Andrew

 

I have a rotary mechanic literally a block from air care. I failed air care first time miserably. Then my mechanic plugged in a garden hose from the intake, directly into the cat (basically it "waters down" the smog). So i passed with flying colors, then immedietely had to return to the mechanic to take the hose out or it would melt. Anybody heard of this? From first hand experience, it was the best way to cheat with a rotary

 

I wish I had both records to show you the huge difference between the two air care reports.

 

Wait, he plugged in a hose, put water in the cat and then you smogged it and you passed? from the intake - split air pipe, are you sure you don't mean smog pump to put air thru it? sounds odd.

 

No "watered down" was a figure of speech. All I know was when you face the hood of your car, in the top left section, he used a hose to reruit air flow into the cat.

 

``My friend'' passed California smog easily last month with ``his'' 87 TII, here were the numbers:

966 RPM
Max Ave Meas
HC(PPM) 120 29 1
CO(%) 1.00 0.10 0.00

2522 RPM
Max Ave Meas
HC(PPM) 140 20 9
CO(%) 1.00 0.10 0.24

All of the under-hood emissions equipment was installed and working, along with a fresh main cat. The car passed with a street port, full turbo-back RacingBeat 3" exhaust, and a CatCo 6007 cat ($47.69 from Summit) in place of the RB pre-silencer.

 

^So he had to get some flanges welded on? did you use the racing beat presilencer flanges? did it directly fit or did they have to put some more piping on? Cause they have direct fit cats on summit for about 100 bucks and some other sights. Thanks

-Andrew