RX-8

iTrader: (6)

HC (gpm) 1.4588
CO (gpm) 25.4526
NOx (gpm) 0.5201
Co2 (gpm) 460.1674

As you might have guess I failed. Do these results mean I'm rich or lean. I'm completely stock except for a downpipe. I've posted before about boost issues and I decided I'm just going to fix the darn thing myself. I think I'm going to do the sequential simplification. My question is has anyone passed an emmisions test with the vacuum simplification? Couldn't find anything with the search engine. Thanks guys

Wargasm

Your car is running too rich according to that.

The most likely cause is that your main cat is not getting enough air added in from the airpump. Is your airpump still connected and working? Is the hose going from the back of the manifold by the firewall down to the main cat still sealed up and working? Did you disable the air control valve?

I'd start by troubleshooting the secondary air injection system in the manual, paying particular attention to parts that put the air into the main cat.

If you can't figure it out, run your tank down to 1/4 tank, dump in 1 gallon of denatured alcohol, and take it to the test FULLY WARMED UP. Don't rag the car out due to the alcohol in the tank, but just drive it around for a NICE while to make everything really hot. A hot engine puts out less emissions, and the alcohol will help get that CO converted to CO2 so you will pass.

RX-8

iTrader: (6)

Thanks for the tip. Air pump is still hooked up. I will check the rest out tomorrow. If this helps there a shhhhhh then woooshhh sound coming out of the engine bay whenever the cars under boost (robbing me of ALOT of power.) I thought that one of my intercooler pipes might be loose but I've checked that 100 times. So now I'm thinking it either the vacuum lines, hince the sequential simplification, or like you suggested something with the air pump. Can I still pass emissions with that sound coming from the engine bay, I mean could it still be the air pump system?

Mahjik

iTrader: (1)

You might inspect the air pump connections. I've heard and seen some air pump connections on FD's that have worked their way loose, causing the air supplied to the cat not to make it there.

Also, the air pump should stop when driving at around 3200 rpms. If you are hearing air noises under the hood after that, it's not the air pump.

The sequential simplification removes parts of the emissions system. If you have emissions testing, I doubt you'll be able to pass legally with it done (meant, you'll have to slip the tester a fitty).

RX-8

iTrader: (6)

Ok, so I guess it's not the air pump. I'll recheck the intercooler piping. Any suggestions on why a stock rx would be running so rich?

Wargasm

it's probably NOT running richer than it should be... Even a teensy weensy bit rich makes it give off lots of emissions so that's why mazduh put on that air pump system... more air means the cat can oxidize more stuff.

If you are 110% sure the air pump system is working right, I'd say the next most likely thing is the cat is just partially dead. Put the alcohol in the tank; I betcha it will pass!

Brian

inis

although this is somewhat unrelated, where does the air pump draw its air from? Where does it suck it all in from? Is it the hose that connects to the elbow right before the Throttle body?

SilverRX7

From the airbox.

SilverRX7

These are my results... apparently lean.... Am I too lean?
What are the targets?

ASM2525 Test(40kph I think)
HC ppm 19
CO% 0.01
NO ppm 318
@2947 rpm
Dilution @ 14.0... <--- I should be closer to 14.7, right?


Curb Idle
HC ppm 33
CO% 0.55
NO ppm N/A
@740 rpm
Dilution @14.9 <--- slightly rich, right?

RX-8

iTrader: (6)

As the emissions station puts it the cut points are

HC 1.00
CO 20.0
NOx 2.3

RX-8

iTrader: (6)

[QUOTE]it's probably NOT running richer than it should be... Even a teensy weensy bit rich makes it give off lots of emissions so that's why mazduh put on that air pump system... more air means the cat can oxidize more stuff.

If you are 110% sure the air pump system is working right, I'd say the next most likely thing is the cat is just partially dead. Put the alcohol in the tank; I betcha it will pass! QUOTE]

...more like 5%. It rained here today as you know, I'll check the airpump so I'm 110% sure! If not, alcohol here I come. By the way Brian, where can I get alcohol or race gas in maryland?

Wargasm

Race gas... I dunno, but that won't help you.

Alcohol is easy. Go down to your local Sears/Home Depot/wherever and pick up a gallon of denatured alcohol. It is around 10 bucks for a gallon I think and you find it in the paint section. Denatured alcohol is generally composed mostly of ethanol, some methanol, some other junk like methyl ethyl ketone I think, and some water (around 5%). If they have different brands and they actually list how much % of each just look for the one with the most ethanol and the least extra junk in there. They ALL have some water in them, don't worry about it. The alcohol "pulls" the water through the system with it and slowly "burns" it off.

Remember you'll need a long funnel or a container with a rubber pouring nozzle to get this in the tank without making a huge mess. Follow my advice above and then after you pass .... go fill up immediately with high octane. This reduces the relative amount of alcohol running around in there because you'll have roughly 1 gallon of alcohol and 16 gallons of regular gas. Drive nice on the car for that tank with little or no high boosting JUST TO MAKE SURE that the alcohol isn't throwing your air/fuel mixtures off by too much. Next time you get gas, most of the alcohol will be gone so you can drive normally with confidence that there is virtually none of the alcohol still in the tank.

Based on your test numbers I'd be surprised if your emissions don't drop significantly if you follow my advice (remember to warm it up very well before the test!).

Post back with your results if/when you get a PASS

Brian

SilverRX7

Is 14.0 dangerously lean for the FD though?

Wargasm

14.0 (if you trust the emissions test gas analyzer) is not dangerously lean for an FD under _cruising_ (vacuum) conditions. 14.0 would be very bad if you were boosting though!

Brian

SilverRX7

Thanks, thats what I thought!!... appreciate the response.