red_dragon

iTrader: (10)

So I failed smog pretty badly today. And also they've lowered all the limits for FDs (wtf). The limits are lower than for the FC across the board.

I have a few ideas of how to fix it, but I'm not sure. Here's my relevant mods:

PFS SMIC
M2 intake
HKS twin power
NGK Plat 9s all around <- I'm gonna go back to 7s and 9s for my retest
Some random catco cat <- (I bet this is a big problem, gonna find a stock cat hopefully)
Power FC tuned by Steve <-maybe running rich?

So here's my numbers
HC 15 mph
MAX 61
MEAS 805 <-lol!

HC 25 mph
MAX 37
MEAS 116

CO% 15mph
MAX .36
MEAS 2.05

CO% 25mph
MAX .35
MEAS .01

NO 15mph
MAX 493
MEAS 594

NO 25mph
MAX 516
MEAS 670

Alright so I'm thinking, I'll do the following:
1) Change to stock cat
2) Change to stock 7 and 9 spark plugs
3) Oil change
4) I've heard of people running more air into the cat by bypassing some sort of air pump relay. Does this actually help since these tests take place under 3000 RPM anyway?

Anyways, any advice would be great. I am WAAAAAAAAAAY off here so my best guess is that the stupid Catco cat isn't really doing much.

Thanks a lot.

Rx7_Nut13B

iTrader: (1)

Also you can run 1 gallon of Reg Fuel to 1 gallon denatured Alcohol.

This has passed alot of cars because it leans the mix out, DO NOT BOOST THE CAR

DaveW

The stock cat with air pump will definitely help the HC & CO readings, but will do nothing, I think, for the NO reading. You need the EGR or a RICHER mixture to do that, IIRC. NO is generated by high combustion temps, which probably means you are already running fairly lean.

Rx7_Nut13B

iTrader: (1)

Alcohol burns cooler then gasoline but takes 2X the amount

red_dragon

iTrader: (10)

So I assume alcohol would help NO since it would lower combustion temps? Do I do:
1) drive around on highway on normal gas for a while. Stop. Turn off engine. Dump in 1 gallon of alcohol and tell him to test it?

OR

2) dump in 1 gallon of alcohol. Drive around on highway for a while under 0psi. Stop. Turn off engine. Tell him to test it?

hyperlitenerd

iTrader: (1)

Sorry to hear that man, I am getting ready to smog mine soon too. Hope you get it figured out. Any problems with visual?

red_dragon

iTrader: (10)

No actually, my guy was like, eh looks fine. But yea not even close to passing the sniffer.

Another question for you guys. If I do change my cat to a Bonez cat, do I need a retune? Or should it be fine?

pomanferrari

iTrader: (1)

You don't need a retune for a Bonez. Here is what I have seen: Set to 0.1 or 0.2 bar for boost, run the "guaranteed to pass" several bottles if necessary (do not run isopropyl alcohol), set the fan to turn on at 100F instead of 95F with the PFC Datalogit, make sure the car is hot right before you get on the dyno, clean out the plastic vapor canister right under the throttle body where the Greddy elbow goes in; new oil change and plugs (7 are hotter) if you need a stock cat, PM me, I have two plus a Bonez.

Natey

iTrader: (19)

Do you still have an airpump/smogpump hooked up? If not, that's most likely the problem...at least it was for me....Mine was intact but dead.

Where in the Bay are you located?

red_dragon

iTrader: (10)

My airpump works...at least I think so. How do I tell lol. But yea this catco is the biggest issue i think. It's really not doing anything.

I'm from South bay.

wstrohm

red dragon,

Yours is the second post I have seen ("Ernesto13B" was the other) that states the 61/27 ppm limits for HC and the lower CO limits also. Something is weird about that; I live in Orange County, CA, and just had our '94 smogged a few days ago. The limits were 88/53 ppm, just like in 2008, and CO% limits were still 0.52/0.50%.

Your car definitely has a problem... my guess would be a LIM gasket vacuum leak, but you probably don't want to hear that. At idle, do you hear any "putt...putts?" If so, a vacuum leak is causing the car to miss, and on every miss, the unburned fuel/air mix from that chamber is going out the exhaust into the cat, and either the cat can't handle it because it isn't getting properly distributed air from the pump, or it's just overloaded with unburned mixture.

I had a minor ("fail") problem in 2002 with the OEM 1994 cat, replaced it with a new Bonez, and failed worse! Installing a stock cat ($1350 or so) fixed that problem. In 2008 our car barely passed (CO= 0.52%) but shortly after that test, I discovered the OEM fiberboard lower LIM gasket had blown out. Replaced it with an updated OEM stainless steel gasket, and our 2010 test shows much better performance:

2010 Emission Specs on a 1994 RX-7 in Orange County, CA - Test Only Station (reason was "High Emitter Profile")

HC (ppm) Max @ 15 mph = 88 - Our '94 measured 35
HC (ppm) Max @ 25 mph = 53 - Our '94 measured 17

CO (%) Max @ 15 mph = 0.52 - Our '94 measured 0.15
CO (%) Max @ 25 mph = 0.50 - Our '94 measured 0.08

NO (ppm) Max @ 15 mph = 704 - Our '94 measured 66
NO (ppm) Max @ 25 mph = 738 - Our '94 measured 128 (Note: our EGR system is removed.)

Maybe you should make a trip south for your smog test, if you can't pass in the Bay area!

scotty305

iTrader: (2)

My car passed smog recently, the max limits were the same as in 2006 and 2008.

Advice already given is solid: make sure the air pump works, fresh oil and spark plugs, make sure the car isn't using an abnormally high amount of fuel (due to problems with air/coolant/MAP/O2 sensors and/or wiring, incorrect fuel pressure, injectors leaking). Stock cat should be warm, they don't function correctly when cold. Idling may cool the cat converter, not warm it up. I don't think the precat makes a difference, haven't tried both with & without to verify this however. The air pump doesn't pump that much air, I doubt it will offset an overly rich mixture. There is no such thing as running it a full blast, the clutch is either off or on... the main difference is whether the air is injected into the exhaust ports or into the center of the cat converter.


I suspect lower limits on are due to failing a previous test so terribly the car is now flagged as a gross polluter. Not sure if this will cause the limits to be permanently low or not, however. Would be really nice if you guys could just fix your cars so they pass and the rest of us don't have to keep taking our cars to Test Only shops due to 'High Emitter Profile.'

Chris_V

iTrader: (6)

Would this help in other cars?

pomanferrari

iTrader: (1)

One thing to note is that if you don't pass your car the second time around, you will now be labeled in the system as a "Gross Polluter" and thereafter, the car will be required to be tested every year.

Don't run isopropyl alcohol or "denatured alcohol". During world war II, they injected methanol as anti-knock for B17 engines. Someone had the bright idea of substituting isopropyl and the engines ended up blowing up. Isopropyl doesn't burn properly compared to methanol or ethanol.

pomanferrari

iTrader: (1)

Here is a paper on adding methanol to improve emission.

10% to 15% seems to do it.

http://www.ripublication.com/ijeerv1/ijeerv1n3_4.pdf

Conclusion
Experiments have been conducted on multi cylinder petrol engine with different
percentage of methanol as additive to gasoline. It is concluded that, the percentage of
additive increases the emission characteristics improved except NOx and CO2.It is
observed that the emission values of The HC and CO are decreased when compared
with petrol. But The NOx emissions are increased due to presence of oxygen content
in the methanol and also the combustion temperature is high. The engine performance
indicating parameters like brake power, indicated power, indicated thermal efficiency,
brake thermal efficiency, mechanical efficiency, etc. have been observed for various
additives at different loads. The brake thermal efficiency increases with increase in
percentage of additive. Thus methanol may be used as a additive for gasoline in
future.

Here is from a Yahoo site: http://answers.yahoo.com/question/in...2184401AATPCu9

Best Answer - Chosen by Voters
What you want to put in it is Methanol alcohol, NOT rubbing ( Isopropyl ), which can have 30% water. You need to look at some of the Dry Gas cleaners, some list Methanol. Other list "petroleum byproducts", those you do NOT want. You want the alcohol, as it adds oxygen to the gas, and helps reduce the emissions. used to be most used Meth, but then they got away from it, but it's made a comeback. Some places sell stuff that SAY they'll help reduce emissions, but I don't see Methanol listed on the ingredients, so I avoid those. I've seen it work, on my old cars, so yes, it can work.
Another item, which is more critical in proportion, is Acetone, virgin ( ie, 100%, not diluted ), 4 ounces per 10 gallons of gas. That also adds oxygen. But 100% is hard to find,and you should avoid it until you read up on it more ( search the Internet for gas mileage and Acetone, you'd find the references ).

Here is an article where a 95.5% isopropyl additive was shown not to improve emission in two lab tests.
http://webcache.googleusercontent.co...ient=firefox-a

After extensive testing, scientists concluded "the fuels containing the Biofriendly additive produced little or no differences in the emissions when compared to fuel without the additive."
Oryxe also sent a sample of the Biofriendly product to the most respected university research facility in the nation at West Virginia University, where scientists ran a shorter, but federally approved test.
"...The baseline fuel that we used with and without the additive was equivalent between each other," said Gregory Thompson, West Virginia University. "...There was no significant difference in the emissions."

MikePhillips

Denatured alcohol is just ethanol that's been rendered unfit to drink. Isopropyl alcohol is usually mixed with water. Methanol and Ethanol would both be OK to cut most emissions, I think. You can mix ethanol leaner than methanol, though. Not sure about isopropyl, or rubbing alcohol. It's often mostly ethanol with some isopropyl alcohol mixed in. Not sure whether it would hurt, or how. But it's usually only 70% alcohol anyway. The rest is water. You can buy stronger stuff but it's easier to just go buy 5 gallons of methanol (same stuff they use in race cars) from a racing shop and add some to your tank to do your test. From what I've read (very new to these forums, and rotaries), rotary engines tend to run pretty rich, so leaning it out for a few gallons probably won't hurt anything. Gasoline needs 14.7 air/fuel ratio to burn completely, while methanol requires about a 5/1 or 6/1. You can lean it out as much as you want and see what happens. If he knew a guy with a garage that would let him test run his car on their smog tester he'd have it made. He could just put 5 gallons of gas in his car and then keep adding methanol until he cleaned up and passed.

I don't know a great deal about smog checks, not having lived in CA for many years, but I will tell you how I used to deal with it: I tagged my vehicle in another state. Wyoming, at the time, was convenient for me.

Speed of light

iTrader: (8)

Actually, the foregoing statement isn't strictly correct. You can change the air pump injection volume in several ways: If you are running a smaller crank pulley on your car, you will likely reduce the air injection volume into the ports and/or the cat (aka, 'split air') and increase emissions. The ACV can and does control the volume of air injected as well as its injection point, so there are several things to check and possibly fiddle with regarding air injection functioning. The best explanation for the air injection system can be found in Mazda's 93 Service Highlights manual. You can search on it for a link, I know someone on this forum has posted it.

When I put a small pulley on the crank, my emissions (HC & CO) went up significantly. I was able to pass CA smog, but only by a narrow margin. If the standards are now tighter, I will have to increase air pump volume in order to pass next year.

Ernesto13B

iTrader: (4)

BTW there is such a thing as running the air pump on full blast, but that wont help to pass smog. When I passed smog back in 2008, I noticed my 02 was 1.00% both at 15 and at 25 mph, and all smog equipment was working properly. When I failed recently, I actually tried running a hose directly from the air pump to the converter just to see if id pass and I ALMOST did. HC's went from 563 ppm to 11 ppm at 15 mph with 02 at 2.43%, but at 25 mph HC's actually increased to 129 ppm. At 25 mph my 02 was 5.50%!! well above what stock should be. I noticed that the higher the 02% from the air pump you have, the lower your HC's and C0 get, but TOO MUCH 02, and they will start to increase AND the converter will overheat. This is why the ACV has the relief valve to divert the excess air back into the intake.

When I had the air pump directing air straight to the converter, my converter was glowing RED HOT. So anybody thinking about doing this. DON'T DO IT! I decided I might as well try it since I knew my converter was already shot. I'm no smog expert, but after all the smog hell I've been through, I've noticed that 90% of all smog problems with RX7's have to do with either a bad catalytic converter, or no air from the ACV getting to the converter, or both. 90% of the time doing a tune up, and changing the oil wont make a noticeable difference in lowering emissions.

Speed of light

iTrader: (8)

Sounds like you're running very rich or have a persistent misfire. 1% O2 in the sniffer tests is about right; even with the extra oxygen you are infusing, that much of a reaction in the converter is pointing towards too much fuel. The good news is that your cat was working; the bad news is that the matrix will soon break up and blow out the tailpipe (or clog). Additionally, and you may already know this, it is preferable to use 3rd gear for the 25mph test if you aren't already doing so.

Ernesto13B

iTrader: (4)

But you missed the part when I said that I ran the air pump straight to the converter bypassing the air control valve altogether lol When I did that, my 02 increased to an insane 5%. However now because you guided me to that service manual highlights, I was able to fix the real problem with the ACV and run the normal amount of air to the converter, and the cat performs normally the way it did before. What i'm trying to say is, do not run a heater hose from the air pump straight to the cat, because you will not pass smog. You will probably just damage your cat trying to pass smog

97SupraTwinTurbo

iTrader: (8)

HC 15 mph
MAX 61
MEAS 805


HC 25 mph
MAX 37
MEAS 116


The HC in the emissions test is high meaning you're running very rich. This could be caused by your spark plugs or tune. Did you warm the car up really well before the test? I would put the other plugs, and warm it up really well and maybe try a higher octane fuel to burn more efficiently. The NOx numbers seem high but not too high, the cat needs to warm up a good amount.

moconnor

iTrader: (14)

This is news to me. I failed several times in a row at my second to last test and did not get called back for the normal two year interval.

Rx7_Nut13B

iTrader: (1)

If you use Higher Octane fuel it will take longer to burn harder to ignite, But Lower Octane fuel will burn quickly easy to ignite

RCCAZ 1

iTrader: (10)

If your plug wires are old, replacing them can help as well.

drakujr

well i passed smog 3 days ago (finally after failing twice) and i also really high numbers. Cant remember what they were and i threw away the papers but i changed the oil, plugs, wires, did a steam clean and am running some aftermarket main cat......then i added the pre-cat and added a bottle (guaranteed to pass).

She passed easily. I dont know if you have the stock pre-cat or not but as far as i know, the pre-cat does most of the work and the main cat burns off any excess. And yes.....warm up the car really good right before getting tested!

good luck