I am about frustrated with the Arizona department of transportation.. For the life of me, I cant get my 7 to pass emissions!! Here is what I have tried:

1. New cats
2. New plugs, wires, airfilter, ACV.
3. Bottles of alcohol
4. Cleaned injectors, tested system.
5. New O2 sensor.

And billion things I cant remember right now.... But I am still failing 2 out of 4 tests!! My best numbers are HC 256 out of 220. And CO 2.01 out of 1.20. I know that my rotor housings are swapped, but it doesnt seem to affect other peoples ability to pass, and my engine is running like a TOP!! And no ECU codes.. Those readings are at 25 MPH...My Idle readings are fine.

WHAT THE HELL IS WRONG?!?!? I am STUMPED!!

 

so they are putting it on a roller??

 

Yeah, and thats where its failing..I am completely lost. The only thing I can think of is a possible ECU failure, since its the only thing I havent replaced. This has me completely lost....

 

Oh yeah...and the horn doesnt work, which also leads me to believe it may be the ECU

 

I am goign to emission this Thursday, let see if i pass. I passed with flying color when I bought the car 2 years ago

 

well ive never heard about 7's not passin emission, im in syracuse ny and they dont do a damn thing besides check the horn lighs and breaks, i guess i should be thankfull ohh i have no idea what should be done to pass i just needed to add my 2 cents

 

Well, the ECU is about the only thing I can think of right now, or the EGR. But I cant be sure and I am running out of money trying to fix this..

 

Hey J-Rat, this thread might help you...

https://www.rx7club.com/forum/showth...ight=Emissions

i personally like the shake hand and give 20... but i'd give 50 to be sure its a gaurenteed pass...

 

The CPU (body) and the ECU (engine) are two different buggers and shouldn't be related.

What are you using for oil? The high HC and CO I have seen related to oil blowby sometimes on german cars (benzs and BMWs) with weak compression.

Are you getting a good spark on the trailing? they help the engine burn cleaner.

Have you tried advancing the timing and cranking back the mixture a little, causing it to run lean? You only need to run it that way for a day.

 

Which would be a LOVELY solution, cause at this point, I am not above bribery...HOWEVER....I the lovely state of Arizona, the emissions stations are state owned and ran, and have a zillion cameras situated about the bays..Not gonna happen for any amount of money. Would running the Airpump straight to the cats be a viable alternative?

 

Oil is brand new Castrol 20-50...and as far as I know, the trailing spark is good. I mean, how can you tell? The plugs are new, NGKs.. Advancing the timing is an option, but the only mixture controls I am aware of are the variable resistor and the idle set screw on the throttle body, and they only affect idle...I cant see how blowby is an issue, the motor is new and doesnt flood. Doesnt even give off any noticeable smoke. It idles smooth as butter, oh and the idle readings are passing fine. Only under load am I failing. Which is why I was thinking of the ECU or CPU....Which ever one controls injector duty cycle. I dont know how to check the duty cycle to see if they are good, but I do know the injectors dont leak, I tested them... I am here to tell you, this one defies logic. I have tried EVERYTHING!!

 

Unplug the secondaires? it won't get any richer at higher RPM (I am guessing with that one, don't know what that would really do)

 

Would you believe I tried that today? But the 25 mph test in 2nd gear doesnt put me near the 3800 RPM mark

 

Hey J_Rat. Seems to me I remember a previous thread where someone (HAILERS, maybe?) stated that due to your rotor housings being swapped, your port air passages on the engine are blocked. If this is true, you have a real problem here. You see, most of the extra air to clean up the exhaust is passed through those ports. There is a split air passage on the ACV, but it is only used in 5th gear (unless the ECU can override it, which I am not sure of). To pass, your best method imho is to rig up something to get port air working again, such as mounting the ACV on a plate with an extra hole drilled to the port air passage and routing this air to the exhaust pipe as close as possible to the exhaust manifold. There may be an easier way, though. Unscrew the split air solenoid valve on the ACV, and remove the guts (Split air is now available in all gears). Next, make sure the nipple facing up on top of the ACV is vented to the atmosphere, not connected to the switching solenoid valve. These steps will cause all secondary air to be pumped to the cat. It will also not be at all obvious that it has been messed with (if you still have a hose connected to the nipple on the ACV). Will it be enough??? I don't know, but it's the best I can offer you right now. Good luck, man.

Irv, Keith's dad

 

well I dunno if u have passed emissions yet...I would suggest rather than worrying about this soo much that ur car doesn't even have nothing wrong really and in the process b4 u go nuts like the dude in the movies "Momento" or Bradd Pitt in "12 monkeys"...go to ur nearby car parts store...tell them what's goin on and ask them to give u that particular fluid that u can put in ur gas tank, drive for about 10 miles and go for emissions testing...I cannot recall the exact name but tell them that u r not passing emissions and I'm sure they should be able to help...hope it works...

 

Which one is the split air solenoid? THe front or back one? And realistically, how much air is supposed to be going to the cats? I have checked the operation of the ACV by taking the split air off the cat, and checking the air flow above 3800. Doesnt seem to be much air going down to the cats. Also, how about directly running the air pump to the cats? Yeah, me and HAILERS had this conversation about my rotor housings being swapped, but his engine has the same problem and he passes just fine. Which leads me to believe that I may have another problem. But I am definately considering a rebuild in order to correct the swapped engine housings. Seems like it may end up being the problem.... I assume that the injector duty cycle is controlled by the ECU. Which is one of the things I havent tried. Anyone know defferently? What about the BAC?

Rat

 

I have dumped just about everything you can imagine into this engine...Alcohol, Garanteed to Pass, STP treatment. Hell, Id probably **** in the gas tank if I thought it would work...

Rat

 

DOyou guys think that tying the 6-ports open would lean out the mix even more??

 

Let me drive it to heat up you rmotor

 

Oh trust me...I have flogged that poor motor to death. Its plenty warm when I get to the emissions station....

 

The last one(N/A) had emission numbers 2 times higher than yours(same test--ASM2525).It had anumber of problems--
1.The clown who installed the motor had the vac lines wrong to the fuel pressure control system-result full 38 psi on the rail all the time(this is unlikely to be your problem because idle emissions appear OK).
2 the water switch was NFG so relief valve dumps air all the time---check this it is a key factor.
3 the ACV appeared to be a bit dodgy,so I arranged the vac line to dump air to split air pipe all the time.To do this lift the front vac line on ACV and plug it with 4mm bolt.
In my case the result was 86ppm HC and 0.1%CO.

 

What is the water switch? And how would you check it? And I failed even though the split air was full time to the cats...

 

Well, I just talked to a guy who says that the AFM could have a weak spring that may be causing the problem...He was the "Head Emissions Guru Dude" at the Arizona DOT. He also granted me a one year waiver to drive the car. SOOOOOOO... Anyone got any AFMs floating around?

 

u got a one year waiver that's nice...now take ur time...do some performance mods...and move OUTTA Arizona the soonest u can...

 

J-RAT, I owe you an apology. We troubleshot your car and determined that your problem is indeed the fact that some yoyo installed the rotor housings *** backwards, meaning the PORT AIR from the acv cannot possibly mix with the exaust. It meets a dead end in the housings. Now the apology is, that I thought my wifes 86 has the same situation, even though it just passed emissions a month ago with flying colors. I tore my intake off to confirm the housings were switched, but no they were not. After swapping in two known good acv and not making the 02 sensor drop to zero or less at idle(it showed .85v, rich, rich), I blew into the passages to make sure they were not blocked like yours. They were not. I put it all back together and pondered. Stared at my rich/lean screw. Seemed it could'nt be that since it was less than half way towards rich. Took the screwdriver to it and turned to the lean range. Instant drop of the o2 voltage from .85v to -.010v. DUH! Shoulda told you, but I was hoping the new cat would get you by emissions. One thought I had on your car was to take a drill and drill four holes in the exaust manifold to match the four holes in the rotor housings. That would let the port air to mix with the exaust. Short of a rebuild, thats all I can think of doing. Might try that on a exaust manifold out of the wrecking yard, or will someone donate one please for this experiment????