I'll try to make a long story short. Today I failed emissions with HC's at 399, and CO at 2.63 making me a gross polluter. I have a random technology high flow catalytic converter, and a working air pump connected properly.

2 years ago, with this same exact setup I passed almost with flying colors. The only changes I made in the past 2 years that COULD have affected smog are that I did a partial vacuum hose job, and I cleaned my EGR valve. NOX is WAY lower then last time which im happy about so I know that made a difference.

I have no idea what happened... the ONLY 1 thing I did notice is that my CO2 was 12.86% @15 MPH and at 25 MPH it was 13.27% doesnt that mean im running rich as hell?

 

Other than the high-flow cat, mods?

 

Hello,

You could start with a good tune up:

1_Oil change (it’s injected directly into the combustion chamber so it’s got to have an impact on hydrocarbons)
2_Spark plug change (if your old ones are dirty this will be to the detriment of emissions)

Then:

3_ 30 min of steady state highway before the test (to make sure the whole system is fully warmed up without dumping a richer mixture in the exhaust)
4_No idle before the test, it actually cools down the cat after running high load
5_You can try to enable the airpump enable the whole rpm range (instead of being [0;3000rpm] make it [0;max rpm]) by bypassing the airpump relay.

Good luck, I have been there, and here (in Canada, BC) they are quite stringent with emission standards.....

 

Silicone vacuum hoses and Aluminum AST, everything else really is stock, besides some non emission related parts like urethane bushings, urethane motor mounts, Oil Pan brace, diehard platinum battery etc One thing I do know is that I have major vacuum leaks even though the car still drives ok and im currently saving my money for a vacuum hose job. I already did vacuum hoses last year, but only a partial job, not full. Over the past 2 years I will say that my vacuum leaks have gotten worse.

Im thinking that the vacuum leaks may be causing me to run excessively rich, is it possible?

 

Possible. Did you mess with the pressure regulator vacuum lines?

 

No, but the nipple on my charge relief valve is broken, so that vacuum hose is just hanging around. Also the vacuum hose that goes from the turbochargers to the pressure chamber is also leading to nowhere and is capped off.

 

To put it lightly, I wouldn't feel comfortable running around with a non-functional CRV.

 

Believe it or not, i've already been saving up for a FULL vacuum hose job. I already ordered a Hose techniques Silicone vacuum hose kit, and I have a new oem FPD, low mileage solenoid valves (x8), a boost gauge and water temp gauge, new waterpump, fuel injector O rings and grommets, Stainless steel OMP lines and theres a few other small things I still need before I get started. I really believe that the vacuum leaks are why im running so rich, since nothing else really got worse over the past 2 years besides that, and I do all the work on my car. While im there i'll replace the O2 sensor as well. Once I get that job done, i'll retest my car (free retest) and report back here with results.

 

GL Ernesto

 

Are you running the Random Technology metal substrate cat or the ceramic?

read
https://www.rx7club.com/3rd-generation-specific-1993-2002-16/why-engine-so-damn-complicated-part-2-emissions-controls-841963/page2/ post 34 and 37 . Metallic substrate cats are undoubtedly better for flow but they do you no favors on emissions tests.

make sure your ACV is working properly

 

I knew the metal substrate converter wasnt the best for emissions before I bought it. I bought the metallic substrate, because I liked the fact that it can handle rich conditions without premature failure, where as the ceramic will be destroyed during rich conditions. I passed smog a year and a half ago with this same converter, just last time I didn't have as many vacuum leaks as I do now. I failed the 15 MPH test with HC's at 399ppm and CO at 2.63%, but at 25 mph in 2nd gear HC's dropped to 52ppm (1 point below the limit), and CO dropped to 0.43 I believe.

I know my catalytic converter and air pump are working, because those numbers would have never dropped that low at 25 mph if they were not. At 25 mph my A/F was 13.27:1 which is pretty damn rich, im surprised I even did that well running that rich.

I also wanna mention that when I passed smog last time, CO was close to nothing, it was about 0.01% and HC's were resonably low, and CO2 was 14.10 which is slightly rich. The only reason why they were so bad this time, was because my CO2 was in the 12-13% range. So I'd have to disagree with that article in that metallic converters cause higher HC's and CO, the only reason why mine are so high, is because im running rich which indicates another problem unrelated to the catalytic converter.

 

As before mentioned, bypass your airpump relay.

I don't know if you can do it like on the older cars. but on my 12a FB I used to bypass the ACV altogether and run the outlet from the airpump straight to the cat. Then the full volume of air is going through the cat instead of a metered amount through the ACV.

 

How do you know the cat isn't going bad? It may not be working nearly as efficiently as it use to be. This is a perfect example of why to keep the stock cat around to swap back during these test. It's way more durable than any aftermarket piece. All the tricks in the world aren't going to make a bad cat work.

 

I feel bad for you guys in places like California.

Here in Idaho, I don't have to worry about emissions testing. (My bigges worry is how to take them off correctly)

I guess its even though since most of you guys don't have to deal with snow for six months like me.

 

I passed Texas emissions last week with a Bonez hi-flow cat and no air pump. The tech "adjusted" the test in order to pass, good luck.

 

You guys wouldn't believe what I THINK may be the reason why I didn't pass smog. Today I received a new O2 sensor that I ordered but I noticed it's 4 wire which is wrong, so I check under the hood to see if it would work but I noticed that my O2 sensor wasn't plugged in??? I found it flopping around, so I plugged it back in. The connection I have is very poor, I'm sure it'll fall out again.

I have no idea how long its been unplugged, but if it was unplugged during my smog test in January, then THAT would explain the reason why I didn't pass, and I was running so rich.... DUH!!! Sure its possible that it unplugged AFTER my smog test, but the chances are highly unlikely. In fact, i'll bet that things been unplugged for months. I'm still gonna do the vacuum hose job first before I attempt to pass smog again so that way it'll be running even better.

I feel like an idiot, that I failed because of something small like that

 

It happens to the best of us. Don't let it bother you too much

 

Ahahah, if we all shared similar stories that wouldn't be the worst one believe me (I have plenty of those in stock). If that's what will make you pass emission then that'll be an easy fix, won't it?

I am surprised you did not have a PCM code or a telltale illuminating on the dashboard.

 

Took the car today for emission testing... Gross polluter AGAIN. Were talkin HC's at 500's PPM. 02 sensor was replaced with a brand new one and is definitely plugged in and I repaired the harness connector. This time, it appears to be there is a problem with the air injection system. The air pump is working (turns on and off depending on engine rpm) but on my smog paperwork, I noticed that my 02 is only about 0.2 percent.

Some of you may have noticed that I had a thread earlier that was describing a high idle issue. I just recently did a MASSIVE job including a full vacuum hose job, fuel hose recall/upgrade, clutch, pressure plate etc. Maby it was a hose I left loose or something, but i'm thinking I can kill 2 birds with one stone here.

Could a leak in the air injection system cause a high idle?

 

Nobody knows???

 

I agree with the previous suggestion that your cat is bad. It probably just isn't working as well as it used to. It's not going to be something little like a vacuum leak although it's certainly possible that your ACV has failed.

 

dont forget that emissions isn't a blanket class anymore, each car has a specific threshold to pass now. I think that was implemented earlier this year. Your cat might have been bad last time but the blanket rule let you slide by that time.

 

I replaced the cat with a highflow metallic substate about 2 years ago. Im not saying its impossible its bad, but if it went bad in 2 years either I have a MUCH BIGGER problem, or that cat was a piece of ****. The ACV may be bad, I didnt think about that. I do remember during my vacuum hose job, checking the ACV and it held vacuum perfectly and didnt leak at all. I also put a new gasket back on it, and remember to reinstall the wagon wheel. ALMOST forgot to do that, but got it back in.

Well before I can condemn the catalytic converter as bad, I need to get the air injection issue fixed, possible leak fixed. I have no 02 getting from the air pump to the cat and idk why. I'm thinking the problem may be more then just that, but I need to start somewhere. Guess im gonna be on my own for this one, thanks for the help.

I hate my life

 

Ok I did some homework and I came up with all the possibilities that could be causing me to rich excessively rich after doing all the recent work on the car I just did: (HC's 535)

(1 Bad Fuel Pressure Regulator
(2 Bad Pressure Regulator Control Solenoid valve or kinked, misrouted vacuum hose
(3 Problem with the fuel injector cleaning?
(4 Problem with the relocation of the fuel filter?
(5 Bad Catalytic converter again
(6 Air Injection issue leak somewhere in the system

I know emission threads are annoying as hell but I wanna at least give ppl ideas so you're not just throwing out possibilities without me saying what my mods are etc. BTW this car is basically stock. The only mods I have are reliability mods: SS OMP lines, Aluminum AST, silicone vacuum hoses, water temp and boost gauge etc, high flow mid cat. FC thermoswitch, etc

Now that I think about it, there really arn't too many things that could be causing the problem

 

so glad I live in an emissions free state