Emissions and Alcohol - how much
 

So, I'm getting pretty close to able to pass emissions. Only HC remains above the limit, so I want to try the denatured alcohol trick.

After reading multi threads about this, I am still unsure about the amount. So, my question is just how much alcohol to gas can one safely run on a Turbo II.

I understand to drive gently to the testing station - 12 freeway miles - and then directly to a premium fill-up - about 4 blocks away.

So, do I run 1:1, 1:2, something else?

Thanks for your thoughts

- k -

I usually run about 3 gal. of gas to 1 gal. of alcohol.

I'll be doing emissions in a week or two myself.

I'm glad there's no emissions here and only a safety inspection

Rotary >Pistons

Run the shit out of it,then put it in AT the testing site just before the car goes in.
Test it,then fill up with good fuel.
Clokker got ya on the Ratio.

I've drained my tank and added two gallons of denatured alcohol. Set the SAFC to make it run and went through with almost zero emissions. I did go through about 10 times that day. After I passed they asked what I fixed. I replied just give me my tags. I paid and when I was on my way out they asked again.... How did you get it to pass? I said "It's running on alcohol and see you in two years!!"

Just to mention that IF you have a proper working system you do not need the Juice.
I bought a 88 vert that Was stored 2 years and had all original equipment on it.I Put in the "works" on Tuning.(plugs,filters,wires.oil change)
It passed no problem.

The problem with emissions as administered in CO is that the result is very dependent on the technician in the car...one with crap manual trans skills will fail you every time.

I'll add a hearty NS to that. I think that guy follows me around (4 fails so far).

Thanks for the input eveyone!

Would still like to hear from more who've used the trick

- k -

Agreed. I've passed multi times with stock FCs; turbo and n/a. Problem this time is my current one has a standalone ECU and I'm having trouble getting tuned just right. It runs pretty good, but just not 'clean' enough for the authorities. No budget for a professional tuner just now and since my daily-driver died (and no budget for another one just now) I really have to get through the test soon.

Just wanted to support the idea that on a stock FC you shouldn't have to do any 'tricks' if you have all the parts working as designed.

- k -

and hopefully they don't remember you in 2 years. just make something up next time.

not much risk, really. these boneheads can barely remember what they had for breakfast.

my friend went thru that with a megasquirt on a miata, he started with a base map found on the internet, and then had to go to the smog place a few times. he basically had to rent the smog machine for an hour or so, so it took a while.

eventually it did pass, although just tuning the AFR to 14.7 won't quite get you there, that's a bit lean and timing matters too

I didn't even know that kind of machine was rentable. Will have to look into that; could be very helpful!

Do you know what the machine is called?

- k -

I went for round two yesterday and I still had extremely high HC but CO and NoX were golden. You think if I wire the Aux ports open it would lower the HC since they never bring the rpms high enough to open them anyway

hope that gets you through, but for me, no can do. It's a Turbo II - no aux ports

- k -

I knew that lol I just thread jacked for a minute to try and get some answers ;)

you ol' thread-jacker you. Hope you do get some answers too.

- k -

wired open auxiliary ports will dirty up the idle, close them and try it again.

Kel, if i were you i would use this opportunity to learn a little about your EMS. just save your original map and keep it safe before doing any tweaking. your obvious start point would be the idle and 1k fuelling maps, lowering the injection figures in the 20-10"Hg ranges until the car runs a bit rough and starts to hunt and then bump them up a tad.

retarded ignition timing actually helps burn the fuel but it depends if they will be actually checking your base timing or not. not talking a huge amount of retard but try 5-10* if it is still having difficulty.

Thanks, I very much appreciate the help and insight you've given me. I am aware that I've probably gotten a lot more help here than I've given. Anyway, I have been reading, tweaking and testing as much as I can over the last year and understand a lot more about this setup than I did (thanks much to you and Aaron).

I'll implement your instructions soon before I try the test again. I think I've got the idle and 1k set well; AFR looks good and it runs well; still, I'll try tweaking the vac ranges you mentioned and see what happens. This graph seems to say that idle and low speed is okay http://kkoop.com/RX7/HCTest2.jpg Something I have noticed which may relate is that the AFR drops dramatically when the injectors stage - 3kRPM.

On the effect of alcohol, a point of interest is this graph http://kkoop.com/RX7/HCTest.jpg (i almost passed that time) This was done with, I think, about 1:2 alcohol, but I'm unsure of the exact amount - I put a gallon in with the fuel gauge near "E". The second one had alcohol, but not as much - the AFRs were reading really high on the way to the test (gauge was blinking red a lot) and I got scared of causing damage, so I put in another gallon-and-a-half of premium (hence my original question of how much one can safely run). That made it much worse as you can see. So, I was thinking that if I put in the maximum safe amount then it might get that extra 0.92 gpm out.

The test doesn't go anywhere near checking ignition timing, so if retarding it can help I can definitely do that.

What I'm trying to accomplish is not a permanent fix, just getting through the test. Right now, the tags are expired and this is the only thing keeping me from getting current and having transportation again; a successful workaround would ease my stress a lot.

Once I'm street-legal, I intend to spend the time and effort needed to get the full potential of the car and make it run right; getting through the next test in '15 without having to do anything but drive my car through would make very happy. I know we all bitch about this test, but being honest, it's one bureaucratic endeavor that I have some respect for. Having lived in Denver when the "brown cloud" was here, and a winter nightmare - late '70s - it is indisputable that this regulation fixed a real problem, and I intend to drive a clean car.

Thanks for your instructions. I'll report back with specifics on what happens.

- k -

Interesting stuff :)

What AFR were you running on pump gas when it failed ?

does the car have a main cat and smog pump still? you won't cause any damage to the engine unless you run it more than a few pounds of boost while on the ethanol(denatured alcohol), which will cause the AFRs to be lean since it takes more ethanol being injected to run properly. you can actually run 100% ethanol but the ECU would need to be remapped to run it, you would then have virtually no chance of failing(operator may think the machine is broken) but i would only recommend making the adjustments for it to pass emissions and then drain the tank and run pump gas again, reverting back to your old map. the ethanol is rather harsh on the fuel system but it will be ok for temporary use. it's actually pretty difficult to detonate while on a heavy dilution of alcohol but better safe than sorry.

i would be more concerned about the operator going into boost(boost cut setting is your friend, set at about 3psi for safety).

it's a little tough to gauge the graph, i'm used to part-per-million of HydroCarbons versus grams-per-mile(weird state Colorado is).

this would be the quickest and easiest way to get you done with it, if your ECU has an enrichment function you can just set it to about 30% enrichment for all fuelling maps.

Neither of the graphs are on straight gas. Both have denatured alcohol; the bad one (hctest2.jpg) is with an extra gallon or so of premium.

AFRs, after warm-up, at idle and before the injectors stage bounce around between 12 and 15. When the injectors stage while accelerating, it falls quickly to 10 - 11 for a bit, then comes back up. At the moment, I'm on straight premium.

When I headed out on the second test, the AFR bumped up around 16 - 17 a lot and the gauge (PLS DM100) showed a lot of red LEDs which made me stop and put in the premium.

.

after he failed a couple (three?) times the smog place offered to let him just tune it on the smog machine.

i've found that the Rotary pretty much falls in line with the piston engine HC/CO/NOX charts. except maybe that the rotary starts lean misfiring sooner than a piston engine.

timing seems to have a larger effect on NOX than the other two, and if the smog place is going to check timing it'll be at idle, and so you just set the idle timing to stock, and then you can do what once its not idling anymore.

Yes, I bought a Bonez High-Flow cat and got Midas to weld it up to fit in place of the pre-silencer. The air-pump has always been there (the previous owner was only part-way though the planned mods) and I studied much on how to make it work by reading through many threads here. Anyway, once I got the air working correctly, the CO dropped down from 50.88 against 20.0 before, to 11 afterward. So, some success there.

That's kinda what I was looking to know...and the plan too. Just want to get through the test and then back to making it operate like it's supposed to.

That's reassuring. I think the plan going forward is to work with your suggestions - especially the boost cut - then go to the test with about a 2:1 ethanol ratio and see what results.

Do you know how to do that on a Microtech LTX?

Yep, no argument there. Not enough oxygen up here...can tend to muddle the brain ;-o

- k -

wow, that's cool! Nowhere near that kind of magnanimity in our guys...they just want to get their 25 bucks and move along.


hmmm...NOX was very okay - 0.5125 against 4.00 - and I don't think they look at anything as internal as timing. The only "inspection" mentioned is Cat Presence:(yep), Air Injection Presence (yep again), O2 Sensor Presense (count 'em - 2), Gas Cap Presence and Integrity (a final yep)

Considering that HC is my only problem now, timing adjustment won't help?

- k -