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Discussion Starter · #1 ·
I don't use the forum much but I'm out of ideas and could use some help.
Some quick info:

---ROM 59580004, tephra v3, running flex fuel, car runs great---

I put the exedy twin disk in about 2 months ago and ever since my CEL has been flashing randomly, and I mean literally randomly: at idle, at cruise, fast flashing, slow flashing; sometimes it flashes a ton, other times not at all. There's no pattern at all.
I've datalogged multiple times and the flashing does not correlate with knock (knock sum = 0). Load req for knock is set 150. I even tried setting the knock CEL flash to 0, and it still flashes just as random. I even adjusted the flex sensor range cel up to 10-15% in case there was something wrong with the wiring and that was causing the CEL flashing. Still nothing.

Again, car runs perfect, doesn't pull timing at WOT, no knock counts anywhere or any time. I feel like since it started with the clutch, it's gotta be something there, but can't figure it out.

Does anyone have any ideas?
 

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Flex fuel will flash when it detects an ethanol percent change. You'll probably see this the most after startup and adding fuel. If you are seeing it a lot, I'd suspect you're picking up some air in the fuel tank.
 

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do you have an ethanol gauge? or if it is the NRG ops flex kit, the wireless app? if so leave that open and drive around a bit, see if the ethanol % changes when it happens.

if i run pump for a while then switch to e, or run some blend (e60 or whatever), i'll get a map switch once in a while driving around leisurely out of boost. it goes away if i up the e percentage on my next fill up
 

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Discussion Starter · #4 ·
Thanks for chiming in @ripnet and @Htothe
I'm running an innovate gauge and sensor kit.
The ethanol content only varies by 10ths of a percentage; for example, i'm around 73% right now so it'll bounce between 73.2 and 73.6 (just a rough estimate, but you get the idea). It's not like a jumps by a full percentage point or anything even close.
I actually haven't put pump in it since it's been tuned, only E with varying content (72-75 more or less).
It flashes on startup of course but it also flashes randomly while driving, sometimes a lot, sometimes a little or not at all. It also seems like it only flashes when i'm in closed loop; if I go WOT or heavy load it never flashes (thankfully cuz that would probably be knock).
Since i posted I've spoken to my tuner again and consulted with another, and they both say this isn't an issue and it's normal. Just seems odd cuz most folks I speak to don't have their CEL flash nearly as much as this, seemingly like the both of you.

Almost forgot to add, I adjusted the flex sensor range CEL all the way up to 100% as a test and it didn't flash at all (on startup or while I was driving). So it's definitely that setting. It's at 2% right now which is the default for most I think.
 

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Discussion Starter · #5 ·
Wanted to follow up here.
I checked everything and cannot find an issue. The E sensor and wiring is all connected correctly and stable. No leaks, no consistent codes (and when I do get a code it doesn't change how my CEL flashes in any way; flashes the same with or without a code).
Everything seems good overall!
I can say that the cel flashing is definitely connected to the Flex Sensor Range CEL function. To test, I adjusted the range from 2% (base value) to 50% and I saw no flashing at all (none on startup or at all while driving). This would tell me that the ECU is getting variations in the average E% reading beyond 2% within the refresh time (set to 400 which tephra reports as roughly 20 seconds). HOWEVER, my gauge (innovate gauge and sensor) reads normal (when i watch it while on the road, i'm only showing e% variations in the tenths, no where near 2% (for example, it'll read between 75 and 75.3 or something; 2% variation of 75 would need to be over 1.5% variation).
Is it possible there's an issue in the harness (from flex sensor to OEM fuel tank pressor wiring)? I'm out of ideas after this...
@ripnet you mentioned air possibly popping in, would those deviations pop up on the gauge or no? If not, I could pull the fuel pump and check the lines there.
 

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I'd assume you would see that on the gauge. You can log Tephra's Ethanol % if you want to troubleshoot further:

<DataListItem DataLog="Y" Priority="6" Color="#000000" Display="Ethanol" LogReference="Ethanol" RequestID="23805083" Eval="x*100/255" Unit="%" MetricEval="" MetricUnit="" ResponseBytes="1" GaugeMin="0" GaugeMax="5" ChartMin="0" ChartMax="5" ScalingFactor="1" Notes="" Visible="True" LogHide="false" />
 
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