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MS3-Idle Issue/VE Fuel Percentage WTF?

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Old Apr 20, 2014 | 12:29 AM
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Exclamation MS3-Idle Issue/VE Fuel Percentage WTF?

Okay... Got Rev built MS3 basic installed. Got it running, but my Fuel VE table is like nothing i have seen. I installed WRX 420cc injectors,set new injector size to 420 and required fuel which is now 7.2....... and my ve table looks like this : MS3-Idle Issue/VE Fuel Percentage WTF?-20140419_231322.jpg

Where i have the arrow hovered over is where it idles at. Why are my fuel percentages so high? i have played with the injector dead time after doing some reading on the WRX forums. Subaru supposedly states dead times of .728, and denso states claims of over 1.0ms. Leaving the dead time at .900 has yielded better VE numbers but not by much. Im used to seeing this in the 30% and 40% at the given kpa at idle. Am i just loosing my mind and being paranoid or is this okay? Also, it has an idle issue, it will run and idle fine, but if you rev the engine driving or not, it has a habit of trying to die and or dying frequently while trying to come back to idle. tried a few things but nothing has helped.

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Old Apr 20, 2014 | 12:33 AM
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MS3-Idle Issue/VE Fuel Percentage WTF?-20140419_233002.jpg first one came out blurry
Old Apr 20, 2014 | 08:41 AM
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were you lean at idle and now richer?

what's the AFR table look like?
Old Apr 20, 2014 | 08:44 AM
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Talked to Gordon at witch hunter, and he told me that dead time for the 11-ohm Light Blue WRX (195509-3920) is around 1.0ms-1.1ms. So I set the dead time to 1.1 in MS3 and everything has drastically improved along with my idle.
Old Apr 20, 2014 | 08:46 AM
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Well my afr tables were fine... I could get 14.7 afrs... it was just the crazy ve numbers that were throwing me...
Old Apr 20, 2014 | 09:12 AM
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This is what my VE Table looks like now, after making the said adjustments and some autotune time:
MS3-Idle Issue/VE Fuel Percentage WTF?-20140420_080137.jpg
Here is my afr table:
MS3-Idle Issue/VE Fuel Percentage WTF?-20140420_080305.jpg
Old Apr 20, 2014 | 12:58 PM
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Anyone know why it backfires at times on decel?
Old Apr 20, 2014 | 05:19 PM
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Because your overrun fuel cut isn't active? Wild guess since there's no .msq to look at.
Old Apr 20, 2014 | 06:52 PM
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Originally Posted by Oscar
Because your overrun fuel cut isn't active? Wild guess since there's no .msq to look at.
Over run is on.... Ill post an Msq soon.
Old Apr 20, 2014 | 10:11 PM
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2014-04-20_20.59.48.msq
Its rough but still working on it, here is the MSQ.... I think i May have figured out the fueling issue, the longer my fuel pump runs, it is gradually loosing its ability to maintain base pressure. I noticed this while driving then coming to a stop and seeing my idle afr's at 16.4. I pulled over and adjusted back to 14.5. Drove a little ways, stopped and checked, and it was back to almost the way it was at 16.4. Drove the rest of the way home and sat in the drive and tinkered with my settings again. While doing so i noticed the fuel pump Un-Loading, then the car dies. Pump still runs but built no pressure. Let set for 30 minutes and its like nothing ever happened. So i ordered a new Walbro 255 and see if that makes things any better. Possibly this dying pump is the cause of the high numbers down low in the VE fuel table? And can someone please help me understand how to adjust these God forsaking fuel enrichments please ! No matter what i adjust, at WOT, im hitting 10's and 11 AFRS and im still N/A...
Old Apr 21, 2014 | 07:37 AM
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why would you order a walbro 255?

and what were you fuel pressures you measure when the fuel pump was "unloading"?

and did you log it to make sure it wasn't any enrichments/corrections/poor tuning?

do you just like wasting money and installing annoying buzzing pointless fuel pumps and not solving problems?
Old Apr 21, 2014 | 08:51 AM
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Originally Posted by Braineack
why would you order a walbro 255?

and what were you fuel pressures you measure when the fuel pump was "unloading"?

and did you log it to make sure it wasn't any enrichments/corrections/poor tuning?

do you just like wasting money and installing annoying buzzing pointless fuel pumps and not solving problems?
By the time i was at a place where i could check, which was in my garage, there car was dead and had no fuel pressure. Pump would come on but pump "nothing" until it sat for 30 minutes. So, to everything else you stated above, no, its pointless without fuel pressure. Wasting money...? Im married so listening to pointless buzzing things that spends my money im used to.
Old Apr 21, 2014 | 08:54 AM
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Originally Posted by jmuse8482
By the time i was at a place where i could check, which was in my garage, there car was dead and had no fuel pressure. Pump would come on but pump "nothing" until it sat for 30 minutes. So, to everything else you stated above, no, its pointless without fuel pressure. Wasting money...? Im married so listening to pointless buzzing things that spends my money im used to.


You've had problems with the pump on this car before too, yes?
Old Apr 21, 2014 | 09:03 AM
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Originally Posted by jmuse8482
By the time i was at a place where i could check, which was in my garage, there car was dead and had no fuel pressure. Pump would come on but pump "nothing" until it sat for 30 minutes.
how do you know this?
Old Apr 21, 2014 | 09:06 AM
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Well... they sell fuel pressure testing kits. I know he's used one in the past on this car.
Old Apr 21, 2014 | 09:08 AM
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Originally Posted by concealer404


You've had problems with the pump on this car before too, yes?
Yeah I have.... It just did'nt click/remember till the problem jumped out and slapped me in the face.
Old Apr 21, 2014 | 09:08 AM
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Originally Posted by concealer404
Well... they sell fuel pressure testing kits. I know he's used one in the past on this car.
Ok. but most people don't just happen to have fuel pressure gauges on their setups to diagnosis an "unloading" fuel pump.

I can think of a few more plausible things within a MS tune that could all the same issues...
Old Apr 21, 2014 | 09:10 AM
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Me, too. Especially considering this is an NB.
Old Apr 21, 2014 | 09:18 AM
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Originally Posted by Braineack
how do you know this?

Took fuel line off the top of the pump/sending unit and installed my T adapter inline with line and pump. Pump turned on but pumped "0"...... I took sending unit out to verify fuel level just in case and i had 1/2 tank like my gauge said.
Old Apr 21, 2014 | 09:20 AM
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Originally Posted by Braineack
Ok. but most people don't just happen to have fuel pressure gauges on their setups to diagnosis an "unloading" fuel pump.

I can think of a few more plausible things within a MS tune that could all the same issues...
Yeah but this was pre-existing condition prior to MS. In all the excitement of installing MS, I had completely forgot. It was the end of last summer when this pump had started giving me grief when it got hot... Then winter came and i drove all winter long and it never acted up. Now that it has warmed up outside the issue has re-surfaced.



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