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-   -   leans out after hot for awhile (https://www.miataturbo.net/megasquirt-18/leans-out-after-hot-awhile-44445/)

jhad 02-28-2010 09:14 PM

leans out after hot for awhile
 
I have a 90 1.6l mspnp, innovate lc-1, no afm It drives fine for the first while of driving then it slowly leans out and no ae's. it seems like heatsoak but my iat shows normal temps when it does it.

help please

Matt Cramer 03-01-2010 11:20 AM

If you could post a data log of the problem happening, a copy of your MSQ file, and a data log of normal operation, I'll be glad to have a look and see what's changing.

hustler 03-01-2010 12:04 PM

Mine does this too after about 10-minutes on the track when its hot out. My sensor is bathed in ambient air too.

jhad 03-01-2010 12:57 PM

1 Attachment(s)
here is the msq im working on uploading the datalog it doesnt want to work yet

jhad 03-01-2010 01:02 PM

1 Attachment(s)
here is the datalog it runs good for the first 3/4 or so then the last bit it goes lean

Matt Cramer 03-02-2010 10:34 AM

It's not really picking up an air/fuel ratio at idle at all, even at the start of the log. Where exactly is the O2 sensor located on this car?

jhad 03-02-2010 11:53 AM

the o2 is right after the header and it shows an afr of 16 at the beginning. sometimes if you dont wait awhile before starting the car the o2 wont change much at first. Its not the beginning of the datalog that matters so much, the car runs fine for the first 3/4 of the datalog its the last 1/4 or so that the problems creep in and makes my idle lean first then my accel enrichments appear to stop kicking in under acceleration

jhad 03-02-2010 08:20 PM

when im driving and it starts to go lean if i turn off the car and turn it back on its fine for a while but then it starts doing it again

sicklyscott 03-03-2010 08:49 AM

i had the same problem for a little while, especially at idle. I changed the sensor and it seemed to clear itself up.

sicklyscott 03-03-2010 08:49 AM

sensor meaning WB02 sensor

Braineack 03-03-2010 08:55 AM

One thing I do notice is you're using a TON of Air temp based enrichments. The whole map has tons of extra fuel being added based on your AIT temps. I'd try making your clt-based air density table all 100% first. However, even though you are adding 41% extra fuel in a lot of spots, yours still pegging lean.

Just looking at your fuel map the values look CRAZY high. I cant understand how you're making over 5mpg.



What happened at 68929 sec? did you stall out? looks like it injected a shit ton of fuel and backfired and kill the motor.

jhad 03-03-2010 11:52 AM

the AIT stuff was just added recently, its not part of the tune regularly, it has been doing this for a long time now but wasnt noticeable until i started getting the car closer to drivable. i changed them back and tried putting it on coolant corrected and my idle got a bit better but it will still do it. my ve values have been based off the ve analyzer . my car has been built to flow a lot more air than stock port/polish, 1mm over intake, glass beaded intake mani., full exhaust. i do believe it stalled out around 68929 sec, the idle was yoyoing a bit when i just stopped in front of my driveway then when i started to drive up the driveway it stalled.

Braineack 03-03-2010 11:53 AM

I wouldn't use VE live with that bad O2 sensor. what sorta gas mileage are you getting?

jhad 03-03-2010 12:00 PM

I don't know for sure i havent cared to check yet

jhad 03-03-2010 12:01 PM

so its my O2 then huh?

jhad 03-03-2010 12:59 PM

so if i turn off my O2 correction than it shouldnt go lean, kinda as a way to check it before i buy a new one

Braineack 03-03-2010 01:05 PM

Well, here's the thing... on that log EGO is only correcting at most +/-5%. So changing that will do nothing. Your AIT corrections however have it adding over 40% more fuel throughout most of the map. I have a feeling the o2 is bad so VE live is adding fuel based off the readings, then to top it off your insane AIT corrections table is dumping in even more fuel, look after 68670sec when the temps hit 90°F, making the thing drive like ass from being too rich.

Disabling o2 will do nothing if the current fuel table has been altered based on false o2 readings.

:2cents:

jhad 03-03-2010 02:07 PM

i have changed the AIT corrections back to the base map settings and it still goes lean doing the same thing. the table works fine for the first 20 min. of driving then it slowly gets lean on idle first then the accel enrich doesnt work so when i accel it leans. it did all of this before i ever touched the AIT corrections

jhad 03-03-2010 02:11 PM

the fuel table itself isnt the problem although it is in need of tuning, the corrections or lack there of seem to be the problem or a sensor

Braineack 03-03-2010 02:16 PM

it's always going to show lean IF you have a sensor that shows lean for no good reason.

Then it's going to run like ass if you tune off a bad o2 sensor that likes to go lean (VE Live will richen the fuel map [and yes your map is bad, it's disproportionally rich as shit in areas it shouldn't be], and then add in a shit ton of extra corrections....uber rich. like bill gates rich. like obama money rich.

or you have a plugged fuel filter or something.


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