Easy2

Hello all,



Well I have just spent the better part of the last few days searching for a means to pass my local emissions test (live in Georgia). I have browsed countless forums and have not found a single write-up for helping a fellow RX-7 owner pass the test.



The metro-Atlanta emissions test consists only of:

gas cap pressure test

visual test to make sure something resembling a catalytic converter is there

~30 second idle test to make sure RPMs stay within limits (500-1000rpm)

15mph dynamometer with sniffer in ONE tailpipe ONLY for max 50 seconds

25mph dynamometer with sniffer in ONE tailpipe ONLY for max 25 seconds



They don't even pop the freaking hood...and if they do, then only to find a spot to put the rpm-gauge-checker-thingy for their computer...



For the following, in case different symbols/words are used on your local tests...

HC ppm --> Hydrocarbons parts-per-million

CO % --> Carbon Monoxide percentage

NOx ppm --> Nitric Oxide parts-per-million

RPM --> Revolutions per minute (duh)



By the way, here are the numbers from my first test, and yes, I made sure car was nice and hot first...drove interstate for about 20 minutes:



50/15 (15mph for 50 seconds)

HC ppm --> Allowed: 180 Reading: 401 FAILED

CO % --> Allowed: 1.01 Reading: 0.78 PASSED

NOx ppm --> Allowed: 1378 Reading: 833 PASSED

RPM --> Allowed: 3000 Reading: 1773 PASSED



25/25 (25mph for 25 seconds)

HC ppm --> Allowed: 174 Reading: 338 FAILED

CO % --> Allowed: 1.12 Reading: 0.64 PASSED

NOx ppm --> Allowed: 1258 Reading: 587 PASSED

RPM --> Allowed: 3000 Reading: 2036 PASSED



Well crap...unburned fuel...I always knew my RX-7 runs terribly rich (250 miles per tank city, but I have a lead-foot too). I just didn't expect by THAT MUCH! So I performed a tune up:



BUR6EQP Platinum City (Hot) Leading Spark Plugs

BUR8EQP Platinum City (Hot) Trailing Spark Plugs

Accell 300+ Ferro-Spiral 8.0mm Spark Plug Wires

HP1004 K&N Gold Performance Oil Filter

Castrol GTX Drive Hard 10W30 Oil Change

WIX Fuel Filter

WIX Air Filter (for stock air filter box)

Bosch 02 Sensor

16 oz. SeaFoam Clean-it-all stuff (poured into gas tank)



Naturally I left all the old parts in while I drove around until my full gas tank with the SeaFoam in it was just about almost empty. I then refilled with 87 octane, put in all the new parts, and proceeded to my second test, again making sure to do some interstate-speed driving for about 20-30 minutes. I left out the air filter for the test (but left the airbox in place) and also snatched off the Power Brake Booster hose on the passenger side firewall. Was hoping the additional air would help with burning excess fuel. Also, had the tester run higher RPMs this time:



50/15 (15mph for 50 seconds)

HC ppm --> Allowed: 180 Reading: 258 FAILED

CO % --> Allowed: 1.01 Reading: 1.13 FAILED

NOx ppm --> Allowed: 1378 Reading: 541 PASSED

RPM --> Allowed: 3000 Reading: 2930 PASSED



25/25 (25mph for 25 seconds)

HC ppm --> Allowed: 174 Reading: 175 FAILED

CO % --> Allowed: 1.12 Reading: 0.64 PASSED

NOx ppm --> Allowed: 1258 Reading: 462 PASSED

RPM --> Allowed: 3000 Reading: 2943 PASSED



As you can tell the Hydrocarbons definitely dropped tremendously. I failed the CO % this time around on the 15mph test, probably because of the vacuum hose I had snatched off from the power brake booster. Well crap...what next...I looked in all forums I could think of (or search for) and couldn't find anything real useful. So of course I figured the De-Natured Alcohol Trick should work. Today I let the tank run down to about 1/8th tank then added 1 gallon of Alcohol, then drove around about 20 miles (spirited driving, no pun intended) and then added 1 additional gallon of Alcohol, and of course drove straight to the testing station for my third test with all vacuum hoses attached and air filter in:



50/15 (15mph for 50 seconds)

HC ppm --> Allowed: 180 Reading: 275 FAILED

CO % --> Allowed: 1.01 Reading: 0.36 PASSED

NOx ppm --> Allowed: 1378 Reading: 762 PASSED

RPM --> Allowed: 3000 Reading: 1837 PASSED



25/25 (25mph for 25 seconds)

HC ppm --> Allowed: 174 Reading: 280 FAILED

CO % --> Allowed: 1.12 Reading: 0.41 PASSED

NOx ppm --> Allowed: 1258 Reading: 131 PASSED

RPM --> Allowed: 3000 Reading: 2041 PASSED



Well %@#$*& I was hoping this time it'd pass. In Georgia you get one free retest (within 30 days) per test paid for, so I was going to use my "free" retest right away (the test tech looked at me funny, LOL) I explained I'd like him to try his hardest to get the RPMs as close as possible to the limit by keeping the car in a lower gear. So he left the car in first gear for the 15mph test, but the %@#$*& couldn't keep it below 3000 RPMs this time around in second gear for the 25 mph test and it reset the whole test twice because he couldn't do it right. He said come back tomorrow and he'd try it again.



Naturally, I'm a little pissed off. I was thinking the higher RPMs would definitely pass me along with the alcohol in the tank and all. The test tech guy said he didn't believe it would pass, since the cycle ran through all the time. Usually, if you have a "clean" vehicle, the test won't even run the full 50 seconds @ 15mph and maybe won't run the full 25 seconds @ 25mph either, because the sniffer tells the computer right away that the car is "good" and the only reason to use up all the time is if the sniffer isn't getting consistent readings and/or the car is borderline PASS or FAIL.



Just a few notes, before any of you start firing off a list of further questions:



The car is COMPLETELY STOCK, with the exception of the plug wires and I also have an aftermarket driveshaft with replaceable U-Joints. The motor has ~30,000 miles on it, and it's a "remanufactured" motor my friend's dad had installed by the dealership for the ungodly $4,300.00 (basically they just use a brand new bare block and water pump, then throw all the other old stuff back on) I of course only paid $2,500.00 for the car after he had all the work done. I've done my fair share of maintaning this gold-digger of a car. Routine oil changes between 2,500 and 3,000 miles. Spark plugs every 2-3 oil changes. Always run 87 octane. Make it a point to get the motor up to 6,500 RPMs at least a few times every time I drive (once it's warmed up, of course!) and tires, tires, tires...



IF ANYBODY HAS ANY SUGGESTIONS, PLEASE HELP!



I realize changing the Catalytic Converter out with a new & improved one will help, but I need a "quick fix" for right now and plus, the car running rich will just kill a new converter again!



*sigh*



AND YES, TPS IS SET RIGHT AND SO IS TIMING/IDLE. I even made the darn tester-light to check if my car had any error codes (none) and for the TPS (One light on no throttle, both lights on with just a bit of throttle, and then only the other light on with a bit higher throttle all the way until WOT) Oh and don't tell me to just undo the muffler from the pipe where he shoves the sniffer into...I think he'd notice with all the extra noise and zero emissions and all...

teknics

i was gonna say do an oil change to help drop the HC's a tad more but you said you did that so im fresh out. Changing the cat would maybe help, but if youre gonna do that go with a nice hghflow, itll still pass emissions plus add a "little performance".



There are other systems people can help you setup with an airpump, i just pay for my sticker in NJ



kevin.

Easy2

Thanks for the reply. I figured getting a new catalytic converter would pass me with flying colors, but I don't have the time / money for the swap. Plus the new one will die a premature death because of the running rich... Have no clue what to do next, other than go back and have the test tech guy run the car at higher rpm in lower gear and hopefully it will pass... Have to run and get more alcohol from the Home Depot or Lowe's. Oh and yeah, the only guy I knew of that you could "pay to pass" no longer works at the same place... Either that, or the law caught up with him, LOL...

Rob x-7

swap out those plugs for stock NGK BUR7EQs and BUR9EQs if you dont have the time or money for a new converter, might want to try some stock NGK wires as well.



perhaps you should do the MMO thing before you change the plugs, allowing the MMO to sit overnight, then driving the **** out of the car to clean it out, then replacing the plugs with the stock 9EQs and 7EQs.



I pass with flying colors running one converter

teknics

wonder if my na could pass without an airpump.



kevin.

DareBee

I have header and complete aftermarket exhaust and pass no problem.

Your airpump must be working properly and I would suggest you make sure your aux ports aren't stuck open (they shouldn't be with your fairly fresh engine). My guy also runs with the tach sensor disabled and runs my car a gear below what the book calls for (it is definately cleaner at RPMs above the bogging range).

Definately put in stock plugs and if your CAT is no good I don't care how little time or money you have YOU AIN"T GONNA PASS.

Either buy a black market test or get the shop to run a clean car using your VIN and license is the only other way to "pass"

j9fd3s

i was gonna say no, but it depends on how tight the standards are.

j9fd3s

couple things. how new is the 02 sensor? does the air control valve work properly? if it doesnt you wont pass. another quirk of these dyno smog tests is that the stock car was never tested like that, so sometimes you have to cheat and rig the acv so that it dumps the air pump air into the exhaust ports all of the time, that should pass you even with a so/so cat.

ColinRX7

Sounds like the exact same emissions standards as Canada





If all else fails, put some methyl-hydrate in the gas tank





Not a good idea by any means, I don't really recommend it.. But if you really need to pass, and it's only for a 5 minute test, dump some in before the test on a 1/4 tank, then drive immediately to a gas station afterwards. Do not drive hard.



Your HC will drop dramatically, but the NOx will raise somewhat.







It's not really THAT dangerous, methyl-hydrate is just "gas line anti-freeze". But I'm talking about using more than just one of those little bottles. Methyl is suppost to really dry things out, it can harm a piston engine if you use an excessive amount, and regularly, for a long period of time. It's kind of unpredictable in a rotary engine, not sure how it will react with some of the internals. Might cause no problems, might cause something undesired. That's why I wouldn't really recommend it, but if you need to pass, it will bring down your HC dramatically at the expense of raising the NOx a little. I did this with a 1989 dodge daytona, it passed. The daytona needed a MAF sensor, and it has about 3x time allowed HCs on my original test. You could really smell the burnt alcohol stink coming out of the exhaust, though. I had an excessive fuel to methyl hydrate ratio. The engine didn't sustain any damage. Never ran different, never burned smoke, never had a problem afterwards, drove it for 8 months before selling it.



It can be risky, I wouldn't recommend it before trying all other suggestions, even then I would think long and hard about it. But it's really up to you. It's been proven to drop HCs.

Easy2

Wow, thanks for all the replies from all of you. Really do appreciate the help!



Well I have looked a little further and also asked on a few other forums and received the same advice as here. The air pump works fine, by the way, and the 02 sensor is brand new. I could not figure out how to do the ACV "stuck open" trick in order for the cat to ALWAYS have air pumped to it. Something about removing an upper vacuum line and capping it... I didn't want to use my 2nd "free" retest if I didn't know how to do it right. Already gone through $45 after paying for two and this next test will be my 2nd free retest (4th test overall)



Anyhow, considering I've tuned this car up and adjusted / replaced everything to the point where it runs better than when I bought it from the previous owner, I guess all that has left me with is the darned catalytic converter. I also considered having the injectors professionally cleaned / rebuilt, but as the FC is my only car, that kind of ruled that out for the time being.



Luckily, I found a very decently priced catalytic converter...or...umm...preconverter AND main converter. This will just be used to pass me through the smog test and as soon as I move out of Smog-testing area, I'll just store it for possible later use:



The price was $140.00 INCLUDING shipping from New Jersey (their warehouse or headquarters or whatever) to Georgia, and should be here Monday. I did the "overnight" shipment, but missed the cutoff for shipping Thursday by a few hours (crap) so it will be shipped today and delivered Monday morning. Here is the link...



http://www.autopartswarehouse.com/cats/par...=2812&year=1988



Not a bad deal since I'm just going to be storing it when not in use anyways. Oh and manufacturer is "Eastern" and had never heard of them prior... Usually they ship you "CatCo" for $175 plus shipping, but they were out of stock. CatCo was same exact design, but will repost on here on Monday after the Eastern part arrives and will run the test and let all of you know how it went... And I'll post my new numbers from the retest.



One last question...Would it be better to run at a higher RPM in a lower gear, or a lower RPM in a higher gear for reducing HydroCarbons? Seems the numbers were way down after my tuneup and 2nd test higher RPMs (without alcohol) and went back up again with everything hooked up right 3rd test lower RPMs (with alcohol)



I am under the firm belief that HIGHER RPMs are better (up to 3000 for the test) but I of course am not an expert...



Thanks again folks, and check out the link...might be worth it just to run the test, LOL.