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Old 04-21-2016, 09:16 AM   #1
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Default MS2 Volt drop + Mental AFR readings

Hi guys

I recently set up my ms2 (db37) and i struggling to lower fuel during idle.

Im running rx8 injector map and data log attached, it will not stay stable and keep dropping rpm, looking at the data log it looks like i have a voltage drop causing a issue too

any help appreciated completely lost!!

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File Type: msq CurrentTune.msq (108.5 KB, 28 views)
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Old 04-21-2016, 09:19 AM   #2
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data log added.

I can smooth out the idle by running silly rich at 10.1 but the bat volt drop is still there and get worse the warmer the car gets!
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File Type: zip new log.msl.zip (538.5 KB, 2 views)
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Old 05-26-2016, 12:32 PM   #3
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Update

I managed to get it running 13/14 however when warm RPM will jump 700rpm to 1100rpm every 2/3 seconds!

it like somthing is taking fuel, if I hold the revs at 2K for instant it will not stay there it will jump up and down 400rpm and afr will drop like fuel being took out!

HELP
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Old 05-26-2016, 03:08 PM   #4
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Old 05-26-2016, 03:43 PM   #5
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Think the problem may lie with the setting here, Injector staging and number of squirts

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Old 05-30-2016, 11:14 AM   #6
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Verify the voltage with a multimeter or something better (if you have one) - the spikes look like they happen pretty quickly, so a multimeter may not actually show them.

However, looking at the log the Dwell is increasing at the same time as the Injector PW, both of which correspond to voltage droops. MAP fluctuations are closely related as well.

If MS sees the voltage is dropping, it will increase the injector dead time (and the Dwell, dwell is logged, dead time does not seem to be) - but if the voltage isn't actually dropping, then it's pumping in more fuel for no good reason, and sending you rich.

It could be something as simple as a battery terminal coming loose.

TL;DR: check the power, it's all over the place, which is making the sensors and the ECU do all sorts of random things.
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Old 06-26-2016, 10:50 AM   #7
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Quote:
Originally Posted by Cus View Post
Verify the voltage with a multimeter or something better (if you have one) - the spikes look like they happen pretty quickly, so a multimeter may not actually show them.

However, looking at the log the Dwell is increasing at the same time as the Injector PW, both of which correspond to voltage droops. MAP fluctuations are closely related as well.

If MS sees the voltage is dropping, it will increase the injector dead time (and the Dwell, dwell is logged, dead time does not seem to be) - but if the voltage isn't actually dropping, then it's pumping in more fuel for no good reason, and sending you rich.

It could be something as simple as a battery terminal coming loose.

TL;DR: check the power, it's all over the place, which is making the sensors and the ECU do all sorts of random things.
Thanks Cus is was a mixture of loose connection and wideband reading rich when it was intact 2/3 points out!
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