Continually leaner AFRs
#1
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Continually leaner AFRs
And now, I'm down to my final problem with the car since the coolant has been more or less figured out.
Right now, if I start my Miata, it'll start at 11.8ish AFR, and when it fully warms up, it will idle at 10.8ish AFR.
If I shut it off for 5 minutes and turn it on, at fully warm, it'll idle at 11.5-12 AFR.
If I shut it off for an hour, it'll idle at ~14AFR when fully warmed up. And it will stay there, even if I drive it for awhile and de-heatsoak the whole SOB.
But wait, if I shut it off for an hour after the previous shut off, then start it up again, it'll idle at ~15ish AFR. And it will stay there, even if I drive it for awhile and de-heatsoak the whole SOB.
I'm 95% certain I have heatsoak issues going on. Since this is the last issue I have with the car that I haven't been able to fix, well, I'm stumped. I want to say it's related to GAIR, but the GAIR most people talk about is only lean restarts, not sitting at the same lean level at idle constantly. Ideas?
Right now, if I start my Miata, it'll start at 11.8ish AFR, and when it fully warms up, it will idle at 10.8ish AFR.
If I shut it off for 5 minutes and turn it on, at fully warm, it'll idle at 11.5-12 AFR.
If I shut it off for an hour, it'll idle at ~14AFR when fully warmed up. And it will stay there, even if I drive it for awhile and de-heatsoak the whole SOB.
But wait, if I shut it off for an hour after the previous shut off, then start it up again, it'll idle at ~15ish AFR. And it will stay there, even if I drive it for awhile and de-heatsoak the whole SOB.
I'm 95% certain I have heatsoak issues going on. Since this is the last issue I have with the car that I haven't been able to fix, well, I'm stumped. I want to say it's related to GAIR, but the GAIR most people talk about is only lean restarts, not sitting at the same lean level at idle constantly. Ideas?
#5
I run ego correction above 800rpm on my MSPNP1 with EV14 injectors. Before I did this, it was a constant battle to manage the idle AFR's...constant tuning throughout the year...and the table IMHO has too few data points which makes it too linear. After enabling ego above 800rpm (instead of 1400rpm), the car runs absolutely fabulous in all weather conditions.
Some will say "Ahaha you can't do that! The computer is too slow and can't think that fast and will 'splode all over the road! AHAHAHA!!!" Well, I'm no electrical engineer, so I cannot confirm that the circuitry can't handle it...however...I am a mechanical engineer, and I can confirm that it hasn't 'sploded all over the road yet, and the engine runs exceptionally well with the ego settings I have used. Note that I HAVE refined the coolant-related AIT correction to get as good as can be within the code, and the ego correction is just that subtle extra compensation to get the idle AFR's perfect.
Some will say "Ahaha you can't do that! The computer is too slow and can't think that fast and will 'splode all over the road! AHAHAHA!!!" Well, I'm no electrical engineer, so I cannot confirm that the circuitry can't handle it...however...I am a mechanical engineer, and I can confirm that it hasn't 'sploded all over the road yet, and the engine runs exceptionally well with the ego settings I have used. Note that I HAVE refined the coolant-related AIT correction to get as good as can be within the code, and the ego correction is just that subtle extra compensation to get the idle AFR's perfect.
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09-05-2015 08:02 AM