m0x

iTrader: (16)

Ok, so I've searched and read through many emission/smog threads for suggestions, fixes, and cheats to pass. I'll start by saying I haven't done everything that has been suggested however the reason for me starting this thread is that I never see anyone post any numbers on how badly they're failing to begin with and what they did to pass (if they ever did) and any numbers if they passed. I bought this car (first 7 and first rotary powered car I've owned) from my friend knowing that it would probably be difficult to pass since I saw the inspection report prior to buying it. I have considered using tricks (denatured alc. trick) but have not yet since I'd prefer it not just be a quick fix; I'm merely looking for suggestions of what to look into next in order to get this car passing. This car is a 1986 N/A with 280k on the chassis and the motor was supposedly installed by Mazda in 2000 and it had about 30k miles on it according to the previous owner before my friend bought it. So anyways, here are the numbers from multiple test, and what's been done in between to cause shift in numbers, etc..

When my friend carried it through inspection the first time it got the following numbers:
HC: 1285ppm (220ppm limit)
CO: 4.17% (1.20% limit)
CO2: (don't have this number, although I'm sure it's high, but no limit is shown)

He was running 93 octane (I know...) but other then that, nothing had been changed from the condition he bought it in.

I bought the car from him well aware of it running these numbers above and discovered a few problems the car was having and corrected them. The brake pedal was rock solid, the vacuum hose above the exhaust manifold had rotted away on the bottom; so I fixed this. Also, the electrical connector to the BAC valve was unplugged, so I plugged it back up and noticed it would now initiate the warm up procedure when cold where as before it just started and idled. I also changed the oil, trans fluid, and cleaned the paper air filter (with air only) until I could get another one in. My dad is a mechanic and has access to a exhaust gas reader at his job and we decided to try it out there before I drove to the inspection station again. It was reading very high PPM (higher then previous #s) at idle and a guy he works with owns a FB so he checked it out and played with a few vacuum hoses around the UIM but the numbers would only drop slightly. So we then nearly fully retarded the CAS and it idled terribly but they told me to take it around the block and warm it up some. I had a difficult time keeping it running when stopping but once I got it back to the shop and tested it read 290ppm for HC test so it was nearly passing. I had noticed engine temperature rising and chose not to drive it to the inspection station and risk overheating it so we advanced the CAS back to its original location (nearly fully advance) and I had it inspected like that.

Here were the results:
HC: 798ppm (220ppm limit)
CO: 1.99% (1.20% limit)
CO2: 11.57% (no prior number to compare to, however no limit)

So it obviously was still not passing but it was quite an improvement. Now recently I have replaced the spark plugs (7EQ & 9EQ), air filter (still paper drop-in), and o2 sensor (Bosch OE direct replacement). The trailing plugs were both mostly black with about 1/4 of the plugs brown and the leading plugs were both completely brown. The o2 sensor had some brown build up and was partial black and brown..
Pictures (click to enlarge):
o2 Sensor:


Trailing Plugs:


Leading Plugs:


I've also had the notorious 3800rpm hesitation, so I went through and re-grounded everything in AaronCake's write-up with the exception of the starter. My ECM grounds were not in the location stated in his article and I was not about to remove the UIM to search for a ground; so I reground the wires coming out of the ECU to the bracket that bolts it into the floorpan. I also adjusted the TPS to be in spec (1k ohm) and adjusted the idle screw. One of the how-to's I came across mentioned adjusting the variable resistor also, which lead me to find out mine is broken. After some reading I saw that people who also had broken variable resistors had simply unplugged them and supposedly the computer resets to a default setting. After doing all of this most of the hesitation was gone and the car seemed to idle, start and just perform smoother in general.

So after doing all of this I decided today that I would drive up to the inspection station and about 5 miles before getting there I would retard the CAS again (only slightly this time) but I left the socket at home and only brought a ratchet and extension *facepalm*. So I had traveled 20 miles to get it tested I figured why not test anyways and see if any improvements had been made from the tune-up...

Here are the results:
HC: 1986ppm (220ppm limit)
CO: 5.63% (1.20% limit)
CO2: 7.61% (no limit)

So obviously my reaction is
I'm really not sure where to go from here, which is why I made this post.
I am not sure on the condition of the exhaust, it is a stock manifold, cat hooked up with split air pipe and what looks to be stock mufflers but with dual outlets on each. The exhaust is relatively loud at the end of the manifold going into the cat, however never owning a RX7 before, I'm unsure if this is normal or not. The precat section appears to be rusting like there are two layers of pipe there and the outer layer is disintegrating. I've not checked the air pump yet either, however when I mentioned earlier that I had temporarily cleaned my air filter until I could get a replacement, I had noticed there was some sort of black sludge in the airbox. It appears to be coming from the hose coming out of the air pump and into the airbox. It was very tacky, tar-like substance and I hit it with brake cleaner and it didn't effect it much. I managed to scrape most of it away with a razor blade but some of it is still there.
(click to enlarge)


So, are there any suggestions?
I've managed to solve all of my problems encountered so far by simply searching but I'm pretty much stuck on this one and any help would be greatly appreciated.

Texas_Ace

iTrader: (18)

Did the car sit for a long time before it was tested the last time?

1 trick/key to passing is to get that cat hot as possible before testing. Drive to the place in a gear to low to keep the revs up and get it hot. Redline it getting close to the station.

The hotter it is, the better.

But also having my first RX7 i don't know anything other than if the stock cats are still on there those could VERY well be your problem. have a shop replace them with 1 or 2 high flow cats. Should cost less than $150 for 1 cat installed.

HAILERS

About the emissions testing......do they just check the emissions at idle or do they check emissions at two different speeds? It would be helpful if you could answer that.

The attached jpg is how Tx does emissions and several other states. The test at 15mph and 25mph. They USED to just test at idle in the bygone good ole days.

I re-read some of your last sentences of your thread. I'd say you really, really, really should consider getting another catalytic converter. An aftermarket one. NOBODY can afford the MAZDA parts. I forget the name of the aftermarket converter I bought. Catco or some such. I'll look it up sometime.

http://www.discountconverter.com/dir...roductID=45700

m0x

iTrader: (16)

The test process is:

-Idle

-2500rpm ( I was once told to rev up 'half-way' and revved to 3500rpm [768ppm test] but the most recent test I was told 2500rpm and did 3000rpm )

-Return/Low Idle (I'm not sure if this is part of the process for sure but I see the screen mention something about low idle for about 3-5 seconds)

-Idle

He also asked if it was a 'dual exhaust' and I explained that it wasn't and that simply splits at the differential.

HAILERS

Is the engine/car in gear when you do those speeds/??????? Are the rear wheels on rollers and spinning?

HAILERS

In most of your thread your not doing any checking out of the ACV or any of the emissions devices. Not good. You need to try to follow the FSM, Fuel and Emissions section, and check out the ACV and related parts.

But on the whole, it sounds like a catalytic converter that isn't hacking it. By the way, the 02 sensor only comes into play if the car is actually being driven. It's out of the loop if not in gear and moving.

m0x

iTrader: (16)

No, the rear wheels are not moving during testing nor is the car in gear.
I've got a Mazda Workshop manual and a Haynes manual so I'll study the emission devices some more and check them out.
Thanks.
Any ideas on the tar-like stuff in my airbox?

NoDOHC

high Hydrocarbons are usually caused by missing. I actually decreased my HC count by increasing fueling (using the Haltech) at Idle.

You need your air pump working (injecting in the ports) and at least one good catalytic converter (two is better).

Basically, if you get bad scores on NOx, CO and HC, it is almost certainly a bad catalytic converter (if the engine at least sounds like it is running smoothly and the ait pump is operating).

The next biggest problem is sensor adjustment (especially the TPS) poor adjustment will also lead to poor fueling which will lead to emissions failure.

Do not premix at all on the emissions tank, get all the cobwebs out of the engine and with good adjustment and catalytic converters, you should pass fine.

HAILERS

There's some general checks you can do that don't require much time and effort.

ACV is on the right side of the engine. I'll assume you know what it is. IF you don't then say so. Anyway, just above the ACV (not on the ACV, above it) are two vacuum lines right next to each other. With the engine fully HOT, and idling, pull one line off at a time. BOTH should have vacuum going to them.

Now pull just the rear of those two lines off while idling the engine. Feel the vacuum on the hose with your finger. At the same time, look on the left side of the engine for a BLUE elect connector which is on the Relief solenoid. Pull that elect plug off the solenoid. When you do that, the vacuum on the hose should Stop.

Do that as a starter. Won't take much time or effort and proves more than less, that the Relief solenoid is working right and the TPS is set right.

Another thing that can be checked real quick. The ACV has a LARGE black hose attached to it on it's side and that hose goes down and fwd in the car. So, you pull that LARGE black hose off and idle a HOT engine. Feel the nipple the large hose was connected to. A slight bit of air might be coming out. Now, reach over there and pull the BLUE electrical plug off the Relief solenoid. When you pull that elect plug off, you should feel a dramatic increase of air coming out of the large nipple on the ACV. Proves the diapharm inside the ACV is good. More later if your interested. This is for a 1986 NON TURBO engine.

Texas_Ace

iTrader: (18)

I will say if he won't that i am not sure where the ACV is, at least i have not heard of an ACV before. I may have seen it but not known what it was.

I also agree it sounds like a bad Cat. So should be an easy fix if that is the case, i plan to have another cat added to mine if i don't pass and have a test pipe made as well so i can remove them when i am not testing.

HAILERS

Here

So, say the things I mentioned all worked. Now with your finger, feel the air coming out the large nipple where the large black hose was connected. A small amount of air might be felt. That's normal. Now reach over to the throttle linkagea and rev the engine over 2500 rpm. About that speed there should be a Real dramatic amount of air coming out the large nipple. If that happens, good.

j9fd3s

iTrader: (3)

if the air pump and acv are working it *might* pass the high rpm test without the cat (its been done) however the idle test is the hardest one, so you actually need the emissions system working 100% for that one

celbii

iTrader: (2)

I've had that tar stuff in my airbox when i first got my 7. It was just rubber from the old airfilter that melted or turned gooey or something.

m0x

iTrader: (16)

Ok, so I tested out the things you mentioned HAILERS.
With the one of each hose off at separate times I couldn't feel much of a vacuum coming coming from the nipples I pulled them from. It seemed barely noticeable at first until I pressed my finger on them firmly for a few seconds and pulled back slightly and then I could notice a slight vacuum. I disconnected the blue plug and it was hard to tell any difference between before and after.

I disconnected the large black hose, and as you said I felt a good bit of air coming out, however when I unplugged the blue plug once again, it made no difference in the output of air. Output did not drastically increase as you said it should.

I reconnected the blue plug and then tried as you suggested in your last post. Air output did increase with RPM.

I was also going to check the air pump too but the hose on the back of it was being a pain in the *** and didn't want to slide back enough for me to pull it off.

Thanks for the reply on the tar-stuff, celbii.
That's most likely what it is.

InsomniacFC

iTrader: (4)

I've had that same tar stuff on a 7 that I had bought that was sitting for a while. If you have time, take off the AFM and make sure it did not slide down there and got stuck on the flapper door. It happened in mine and the car ran really odd until it was cleaned out. IIRC some simple green did the trick.

+1 on the bad cats. My old stock 7 (3 cats and OEM mufflers) was not that loud at all. My gutted cat 7 was really loud.

Lastly, the denatured alcohol trick will take the HC level down +- 100 PPM with a gallon of alcohol in a quarter tank of gas. I did a test with and without it if anyone calls BS.

HAILERS

[QUOTE=m0x;8390369]Ok, so I tested out the things you mentioned HAILERS.
With the one of each hose off at separate times I couldn't feel much of a vacuum coming coming from the nipples I pulled them from. ************************************************** *************

Just in case: It's the small vacuum hose(s) that will have the vacuum, not the metal nipples, when talking about the two small hose. I'm a little bit up in the air about whether you were checking for vacuum at the hose or the metal nipple.

It sounds to me like there is maybe a problem here. Those two vacuum hose are what Control the ACV. The ACV is what sends air to the Exhaust port in the engine. It sends air there to get the mixture of gases coming out of the Exhaust closer to a 14.7afr, vs not having any air injected into the exhaust. There's a purpose to doing that. The catalytic converter is more efficient when a mixture closer to 14.7 afr is seen vs a richer afr.

Maybe this will help. See the three small hose on the front of the dynamic chamber??? One above the other? One hose is larger than the other two. Well, if the other two hose are swapped with each other, then you won't get vacuum to the tubing that goes to the BLUE relief solenoid and so it won't work right. Anyway, the BOTTOM of those three hose, should route down and then to the left side of the engine. The middle hose routes down and to the right of the engine and goes beneath the dynamich chamber area.

So..........look and see how those two hose are routed. If still not sure, swap the two small hose and then get the engine hot and idle it. Then repeat the procedure in my other post above. I mean pull the two hose above the ACV off one at a time and feel for vacuum on each HOSE and see if things are different or not.

I think you probably were checking the hose. Not 100% sure.

About those three hose on the dynamic chamber.........not all hose coming off the throttle body are vacuum. Only that bottom hose. The middle hose and large hose are not getting vacuum from the throttle body.

HAILERS

Opps. This is the ACV internals I meant to post above.

I don't know if this will make sense to you are not. ON the left you see the Relief solenoid and a pipe from it to the ACV. If vacuum is on that tube, then the diaphram inside the ACV will be pulled left and in turn cause a poppet valve to pull left and not allow air to go out the air silencer. When you pull the BLUE plug off the relief solenoid, then no vacuum goes the diaphram and a sping inside shoves the poppet to the right and now allows the air from the airpump to exit the air silencer. Just follow the red dots from the airpump to the air silencer.

When vacuum is coming from the relief solenoid, then the passage that goes to the air silencer is blocked and now air is routed from the air pump to the PORT AIR passage you see to the right. That air goes directly to the Exhaust Ports and mixes with the exhaust gas coming out of the engine to reduce the afr prior to going to the converter.


Anyway, here's another idea or THING. Say you had a spare piece of vacuum hose. You could put it on the rear metal NIPPLE of the two hose just above the ACV. With the engine idling, you could suck on that spare hose while feeling the air blowing out the LARGE nipple at the bottom of the ACV. When you suck on the spare vacuum hose, the air coming out the ACV will be reduced. When you quit sucking on the spare vacuum hose, the air will increase coming out the LARGE nipple on the ACV. Proving the diaphram inside the ACV is good. IF you suck on that rear nipple and it won't HOLD a vacuum, the internal diaphram is kaput.

BY the way, your airpump is probably good so don't ruin the hose that runs from the airpump to the ACV. When you rev'd the engine while feeling the air coming out the LARGE nipple, and felt a large volume of air come out, that proved the airpump is most likely very good.

HAILERS

Tell you what. Just to check to see if I have a faulty memory, I just went out to my 86non turbo car and followed the procedure I outlined in my first or second post.

The Engine MUST be fully warmed up to do this. So fully warmed up, I pulled the rear of the two vacuum HOSE off that are just above the ACV. I had no problem feeling vacuum on that nipple at idle.

I put that hose back on. Then removed the LARGE black hose and put a finge in front of that large metal nipple with the engine idling. Then I pulled the rear of the two hose above the ACV off. When that hose was disconnected, I can feel a definitly larger amount of air coming out of the LARGE nipple on the ACV. That's at idle.

Just curious. Fully heat your engine up. Go to the BLUE connector on the relief solenoid. With the engine idling, pull the blue plug off and put it back on several times. Can you feel a *clicking* of that solenoid when the plug is pulled off and put back on? Should.

drift2k

I'm not gonna read through this whole tread lookin to see if my answer as allready been said BUT

My Verts Co was at 9.22%! Sounds like im talkin out of my *** but im not. Threw a bottle of rubbing alcohol in my tank while Empty then filled er up with premium and the guy testing it honestly freaked out telling me He's never seen someone fix a car that horrible in unber 15 minutes lol.

I then of course fixed everything when i had the cash. Kinda....

Oh I also has all my emmissions crap disconnected cause they like to catch on fire.......3 times......In one day

m0x

iTrader: (16)

Thanks for your help so far Hailers..

I checked both the nipples and hoses. That explains why I didn't feel much vacuum, or well, what I thought was vacuum coming from the nipples. I don't believe I felt anything from the hoses either; which would be explained by the paragraph below that your process you posted earlier helped me discover from what I understand.

Here is what I found; before even swapping them I followed each hose and it does appear the middle and lower hoses were backwards. The way it was hooked up, the middle hose ran down and into a hard-line which went to the driver-side of the engine. The lower hose and upper hose both ran down then over to the passenger-side of the engine. I didn't get a chance to swap the hoses because the one hooked to the middle running to the hard-line ended up breaking where it met the hard-line and I pulled it off; it is very brittle. The other lines are still soft enough to maneuver around without breaking, however until I can replace the broken vacuum line, moving them probably wouldn't do me any good.

Here is a sketch of how it was setup in case my explanation was unclear:
(Click to enlarge)

HAILERS

Yeah. Those two lower hose were on wrong. By the way, just go to the auto store and buy some vacuum line for windshield wipers etc. It works fine for a decade or more. No sense in buying pretty colored hoses (silicone hoses).

When you get the new vacuum hoses, and put them on right, the engine should idle better. I've swapped them before on purpose and that's what I observed.

The middle hose goes to a nipple b/t the two oil injectors on the lower intake manifold and that nipple leads to the fuel injector air bleeds. The fuel injector air bleeds actually pull vacuum on that hose, so if you had them on backwards you would have a bit of a vacuum on the relief solenoid. Not much, but some vacuum.

Someone else on this forum had emissions problems and we found the same problem on his engine. He passed the next time he tried. He had to do the 15 and 25mph on rollers emission test.

All that bs said, if this is the original converters on your car, I don't think you'll pass without changing them or just buying the MAIN cat and leaving the other ones in place.

After replacing the vacuum hoses, try the procedure I wrote in one of my first posts again. Engine must be up to temperature. If it isn't, the water temperature switch on the bottom left, aft side of the radiator will not be *made* and prevent the Relief solenoid from closing. I'll try again, it'll de-energize the relief solenoid til the temps get up above a set temp. I forget what temp right now.

I think that's COOL AS ALL GET OUT, that you found those two hose on the front of the dynamic chamber crossed. They're easy to get crossed. Too easy imho.

m0x

iTrader: (16)

Ok, so I fixed the line and it idles much smoother and slightly higher then I had it set. It's now around 1000rpm at idle. I repeated the process above and here is how they each turned out (I left the idle at 1000rpm during these tests):


Only the rear line has vacuum when performing this test.
Just for clarification it is attached to the top-rear nipple leading behind the motor and the front nipple's hose is attached to the lower-rear nipple leading behind the motor.


Only the top-rear nipple has vacuum and it was uneffected when disconnecting the blue electrical plug.
The bottom-rear nipple had no vacuum and did not change either.


There is a slight bit of air coming out at idle and airflow was not effected when the blue electrical plug was disconnected.


There is a drastic increase of air when the engine is revved.


The air output was not changed after disconnecting both hoses.


I had a difficult time hearing if it was clicking or not while doing this. I could not feel any clicking either when resting a finger on top of the solenoid; however I could feel/hear it when I cut the car off while leaving the ignition in the run position, with the car fully warmed up prior to shutting it off, and did feel/hear the solenoid clicking.

HAILERS

With a fully warmed up engine, both those vacuum hose above the ACV should have vacuum. One comes from the Relief solenoid (Blue elec plug) and one from the Switching solenoid (grey elect plug). Just FYI.

I'll figure out something later. Gotta go rowing. Later.

Do you have a digital meter?

HAILERS

Here are a couple of jpg showing Where the vacuum comes from that SHOULD be on the two small hose above the ACV on a 86 non turbo car.

So, there are several ways to play this. You have only one hose that has vacuum on it above the ACV. So idle the engine, then go to the solenoids and pull the OUTPUT hose of each one at a time. When the vacuum disappears from the only hose above the ACV , then you've found the source of THAT vacuum.

I forget which hose has vacuum on your car. The rear hose goes to the Relief solenoid and the front hose to the Switching solenoid. That is the way it SHOULD be. But you can see those two hose can be swapped real easy. That swap would not explain why BOTH hose don't have vacuum.

You also could check the vacuum in hose on each to see if each has vacuum coming into the solenoids.

IF you have a digital meter, put it's negative lead on a known ground. Then with a fully HOT engine, back probe the GREEN/RED wire of the TPS connector. The half of the TPS connector that is a part of the EM harness, NOT the half going directly to the TPS. It should read approx one volt dc. If not, screw the screw til it does read one volt dc. NO connectors are to be apart when you do this and the engine MUST be fully warmed up. Gotta go now.

Your starting to see why some RX can't pass emissions to save their life. The vacuum hose and other items have been MESSED WITH.

HAILERS

One more item. All those solenoids are the same item. BUT some are configured differently by moving the round filter to one solenoid nipple to the other nipple. When you lood at a Relief and then a Switching solenoid, the FILTERS should be in a different location on each.

The Relief has it's filter under the BLUE electrical plug. The switching has its filter on the inboard side of the solenoid. Maybe someone has put the electrical plugs on the wrong solenoids or has installed the wrong solenoid in the wrong place? Never can tell til you look.

And as an aside, see how my CAS cinch bolt is in the corner of the slot in the CAS instead of closer to the center of the slot? That is what happens if you put the CAS drive gear, located on the eccentric shaft, on *** backwards. Just FYI.

OH. And this is semi important. What is your idle speed? Plus or minus fifty of what it is will do.