I need tuning help!
 

Soo .. my car failed emissions testing.

I live in Gburg, Maryland. I need help. Can anyone in the area meet me ... in the area to help me with tuning MegaSquirt? I'd like some in person help.. cause this isn't working too well on my own :(

1995 miata, 1999 engine, FM turbo

It runs ... but is spewing out too many bad stuff to fail emissions. And first starting doesn't seem to stay alive all the time. BUT it runs and runs fairly well!

Just got a new battery .. that solved some issues. But I need help with the finer qualities of MegaSquirt ..

sooo .. anyone able to help me?!

Datalog and tune?

register tunerstudio, use autotune.

^^^What he said. Pay for TS, totally worth it.

If MD does the test like VA does it, on the rollers at 15 and 25 mph, just set your AFR target table to 15.0:1 everywhere under 3500 rpm and under ~60 kPa (the test only hits part throttle/cruise cells, I datalogged mine last month), drive around for a bit so the autotune can do its thing, and you should be good. Use the ignition timing table from the DIYPNP base map. Assuming you have a cat, you should pass.

There is also a dyno day in a couple weeks up in MD, should be a few MS users there.

ok ... cool.

I paid for tunerstudio already.

MD emissions test is hold at idle for a couple min. hold at 2500RPM for a couple min, repeat 2 or 3 times.

Thanks for the tips. I'll give them a shot.
AFR to 15:1
base DIYPNP spark map.

cool.

I do have a cat. hopefully i haven't ruined it yet!

should i do anything to acceleration enrichment settings? would it dump extra fuel when i first jump to 2500rpm?

not sure i'm free for the upcoming dyno days. so if anyone in the area is free and nice enough to meet up sometime in the near future to help me out a bit (not necessarily with the emissions specific tuning) with general tuning issues.. that would be awesome.

~andrew

Do you know how you fell the test? What you didn't pass?

my parents garage is in Gaithersburg so I go there fairly often. I never did the MD emissions (91 car = historic tags) but I could probably help you.

Dyno day is on the 15th

that would be cool! think you'll be up by this area at all this week or weekend?

as for the dyno day .. the 15th i'll be up north a couple states.

and for failing... i have that data. Forget exactly what it was... should only be two reading that they take from the tail pipe and i failed both with flying colors.
i'll add tonight the specifics on what i failed tonight.

ok .. here's where i failed with emissions:

HC(ppm) = 376 (passing level is 175)
CO% = 2.40 (passing level is 1.00)

so yea .. i done real bad

HC is pretty high.. is the car burning any oil?

i think it's only leaking a little oil.. but burning any. I haven't noticed any puffs of smoke coming out of the tailpipe.

Are you positive your AFRs are correct? These numbers suggest you are RICH.

I'd double check my calibration.

Also, when you fit this new motor, did you resync the igntion timing?

Yes, high HC plus high CO = rich. Damn, what kind of fuel mileage do you get? Because you haven't posted a datalog or your .msq, we can only guess as to what AFR you're running, but if we're gonna play the guessing game I would guess you're running in the mid-13s based on those test results. You need to set your sub-100 kPa AFR targets to resemble something like these in order to not spew pollution all over the place while cruising along at part throttle.

https://www.miataturbo.net/attachmen...1&d=1314850945

Do a free air calibration of your wideband beforehand if it's been a while since you've done that, also verify that your MS-commanded timing is sync'ed to the motor like Brain said, and then autotune for a while using those targets. Based on your posted test results, the autotuner should want to pull several points of fuel in the areas of your VE table that correspond to the red-to-orange-ish areas of the above table.

oops .. in my previous post .. meant to say NOT burning oil.

soo .. maybe my target AFRs are the problem.. haha

Scott, my table doesn't look like the one you posted below. I don't have mine on this computer .. but I'll post it tonight.
Is the AFR table you posted for every day driving or just to pass the emissions test? I'm pretty sure my table is 1-2 points lower under 75kpa and below 3500rpm.. oops!

I haven't been able to drive the car too much recently .. so I have no idea what the mileage is like. I can only assume it sucks.

I'll post an MSQ and datalog when I get a chance .. hopefully tonight.

Yes, I guess I'm running very rich. AFRs during the test were at high 12s to mid 13s.

with the new engine put in .. timing was checked and set in tunerstudio.
wideband O2 sensor calibration was done a month or two ago .. but i've only put 40 miles on the car since then. but i'll recalibrate before doing anymore testing

I like his AFR table; I'd just make my 75 kPa row look like the 55 row, and bump the 75, 80, and 100 kPa rows up one.


AFRs should be around 14.7:1 during the test, that's the issue, just run autotune.

Don't bother recalibrating the WBO2, it's been done recently enough. Just tune to a proper AFR and you shouldn't have to do anything else to pass the test.

And I use that AFR target table 100% of the time- daily driving, track days, smog test, all of it. Well, for my recent smog test I changed the 15.x cells to all be 14.7 because I thought my NOx would be high with 15.x, but changing it to 14.7 actually made things close to the rich HC limit (barely passed at 2500 rpm). It would have been better to leave that table exactly as shown with the 15.x cells.

thanks for all this. I'll try to get some tuning in tonight and see where it goes from there!

Another factor that help lower the HC count is clean oil.

There's less than 300 miles on the current oil.

ok...didn't make it out last night for a test run. but attached is my current msq. what do you think?

also attached is a picture of my current afr, fuel, spark. i guess my afr isn't as far off as i thought it was.