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DIYPNP Won't Stay Running

Old 09-12-2015, 05:36 PM
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Default DIYPNP Won't Stay Running

DIYPNP built by Braineack. 1995 N/A Miata, stock FP, stock injectors. GM AIT. Fixed timing set in TS to 10.

Can get it started, but it idles rough for a few seconds and dies. I can give it some gas, and it'll run, but as soon as I let off the gas it dies. Not sure if this log works, attached.

Help?
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File Type: msl
2015-09-12_16.27.05.msl (137.1 KB, 96 views)
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Old 09-12-2015, 06:00 PM
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Where is your wideband?
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Old 09-12-2015, 06:01 PM
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No wideband. I thought I'd set TS to use narrowband.
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Old 09-12-2015, 06:06 PM
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So you use a narrowband and absolutely no tuning, obviously?

Wow, wonder why it don't work.
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Old 09-12-2015, 06:08 PM
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Yes, stock O2 sensor. And yes, obviously no tuning, since I can't even get it to stay running. Thank you for your help.
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Old 09-12-2015, 06:18 PM
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If you had a wideband you could tell what was happening while the thing was running then you could adjust it after it died, tuning.

You will never get it right without a wideband, you should go back to stock till you can afford to do it right.
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Old 09-12-2015, 06:32 PM
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So basically you're saying you can't run a MS without a wideband?
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Old 09-12-2015, 06:44 PM
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Does that really need to be said? Is it not obvious already?
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Old 09-12-2015, 07:03 PM
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Guess so. Thanks again for being so helpful.
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Old 09-12-2015, 09:49 PM
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what happens if you increase your req_fuel to say 15?
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Old 09-12-2015, 10:09 PM
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It idled very roughly once, then wouldn't idle again.
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Old 09-12-2015, 10:28 PM
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the PW on those logs is really low. I wouldn't expect it to idle lower than 1.6ms or so, im seeing it dropping down to .9 in that log.


under fuel settings and injector dead time. can you put the deadtime value from .850 to 1.2ms.
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Old 09-12-2015, 11:01 PM
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Pretty much same result. Rough idle for a while around 400 rpm, then won't idle at all. Not sure if attached log helps.
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File Type: msl
2015-09-12_21.57.12.msl (161.9 KB, 89 views)
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Old 09-12-2015, 11:20 PM
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Is your MAP sensor calibrated correctly? You shouldn't be seeing over 100kPa. Also there's no real point in using the ECU until you get a wideband or you're not going to be able to tune it.
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Old 09-12-2015, 11:55 PM
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How does one calibrate the MAP sensor?
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Old 09-13-2015, 09:46 AM
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looking at the log, what it really seems like is that the idle valve isn't doing anything. it's pegging open to its fullest but your idle speed is unaffected. But even still, your min. idle speed should be like 600-700rpm, not 200-300.

it IS really hard to see what's going on with fuel without a wideband.

Last edited by Braineack; 09-13-2015 at 11:27 AM.
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Old 09-13-2015, 11:08 AM
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Have put back to stock til I have time to route WB wiring.
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Old 09-14-2015, 07:34 PM
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Originally Posted by huesmann View Post
How does one calibrate the MAP sensor?
So how you you calibrate the MAP sensor?

I assume nothing further needs to be done for the AIT other than Tools>Calibrate Thermistor Tables>Air Temperature Sensor>GM?

Is there anything different for MAP? Tools>Calibrate MAP/Baro>??which selection?? Maybe that's my problem, incorrect MAP selection?

Last edited by huesmann; 09-15-2015 at 03:36 PM.
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Old 09-14-2015, 07:55 PM
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should be set to the MPX4250, but opening your project here, it might have be set to the 3bar for some odd reason...
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Old 09-16-2015, 08:11 PM
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OK, still no WB installed (waiting on O2 sensor socket/wrench), but with AFR and EGO Control set to Narrowband in TunerStudio, setting Calibrate MAP/Baro to 4250 gets it to idle, albeit roughly. I guess that's progress?
Attached Files
File Type: msl
2015-09-16_18.55.04.msl (391.7 KB, 97 views)
File Type: msq
CurrentTune.msq (110.6 KB, 115 views)

Last edited by huesmann; 09-16-2015 at 10:27 PM.
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