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Hey guys. So im on e85. On my 5th tank of it. It is very good pump e85 (readout 82 to 86).

When i start the car it it always in the 80's. I can drive around for an hour and it'll still read low high 82 85. Perfect. Then randomely it'll show low 28.

At some point wether it be during idle or cruise or coming to a stop or whenever it saw a low spike of 28 hence why it registered 28 on the low reading.

Does not matter wether i cruised around or floored it. at some point it'll show me a 20' 30's 40's low. This must happen within a second because i do not see the main readout ever go below 82. Its only the small low readout that will show it out of nowwhere

Is this a possible cobb glitch? Im on the 5th tank of E. There is absolutely no 93 left in it.



Heres a pic thanks guys
 

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Hey guys. So im on e85. On my 5th tank of it. It is very good pump e85 (readout 82 to 86).

When i start the car it it always in the 80's. I can drive around for an hour and it'll still read low high 82 85. Perfect. Then randomely it'll show low 28.

At some point wether it be during idle or cruise or coming to a stop or whenever it saw a low spike of 28 hence why it registered 28 on the low reading.

Does not matter wether i cruised around or floored it. at some point it'll show me a 20' 30's 40's low. This must happen within a second because i do not see the main readout ever go below 82. Its only the small low readout that will show it out of nowwhere

Is this a possible cobb glitch? Im on the 5th tank of E. There is absolutely no 93 left in it.



Heres a pic thanks guys
Which flex fuel kit are you running? I noticed on a friend's car that his would do the same thing, but it would only occur when the car sat turned off for an hour or so, and the coolant temp got down to the 120s range. This was something that only was there for startup, and would clear once the fresh ethanol would circulate through.
 

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Discussion Starter · #3 ·
Im on viscontis kit. Its actually fine when started up... Car could be running for an hour and it'll randomely show during driving.
 

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Cobb Tuning
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Its possible that the sensor is send that reading out temporarily during a brief moment due to fuel cavitation at some point. We are actually just finishing testing on a few new features which would invalidate that reading and it would never be displayed on the ap unit. This will be out with out next software release and you will just need your tuner to update the map for you. You currently shouldn't see any ill effects from what you are describing, but no worries it will be fixed soon.
 

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Yep I got that same readout too while driving, but car still pulls hard and no knock, so I shrugged it off as a glitch...

Sent from Galaxy NOTE 5
 

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Have your tuner bump your fuel pump duty low to 50%. That should resolve your issue. Hot fuel just spitting is what is causing the jumping E%.
 

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Discussion Starter · #8 ·
Have your tuner bump your fuel pump duty low to 50%. That should resolve your issue. Hot fuel just spitting is what is causing the jumping E%.
Rob that would be low duty pump spitting hot fuel while cruising? Would not affect car when WOT and both pumps r running load?
 

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Very possibly. I would log it. The log will catch the jump. I bet it goes away once your moving and fuel temps stabilize. I doubt it's present on cold start either. I don't mean to be contrary to what Cobb says but I have felt this E% jump in cars while driving, so it is actually a real issue not just to be swept under the rug. I alerted them to this well over a year ago. Shrug..... It's NOT JV's kit either I promise you that.

The primary pump runs at 3 cycle. Low, medium, and high. Low is for idle and cruising. RPM and engine load dictate the when the pump jumps to the next voltage increment. At WOT the pump runs on high. The secondary pump only really runs on high but it does have a 2 cycle setup low and high. All of these parameters should be available in Cobb's software. I live in the land of EcuTek with the GTR now, but last time I looked they had the needed tables.
 

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Discussion Starter · #10 ·
Very possibly. I would log it. The log will catch the jump. I bet it goes away once your moving and fuel temps stabilize. I doubt it's present on cold start either. I don't mean to be contrary to what Cobb says but I have felt this E% jump in cars while driving, so it is actually a real issue not just to be swept under the rug. I alerted them to this well over a year ago. Shrug..... It's NOT JV's kit either I promise you that.

The primary pump runs at 3 cycle. Low, medium, and high. Low is for idle and cruising. RPM and engine load dictate the when the pump jumps to the next voltage increment. At WOT the pump runs on high. The secondary pump only really runs on high but it does have a 2 cycle setup low and high. All of these parameters should be available in Cobb's software. I live in the land of EcuTek with the GTR now, but last time I looked they had the needed tables.
Much appreciated rob
 

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GTRLIFE BOTM August 2015
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Here is what I've found and heard. Mind does it every once in a while (Gotboost kit on Cobb). I logged it and it won't happen under acceleration...only when cruising or idle or decel. I was told it's an air bubble that sometimes hits it on the return. The Cobb sampling rate is incredibly fast and as such it never misses a beat. I heard Cobb/Gotboost was looking at a slower sample rate to eliminate seeing these.

Who knows how much of the above is accurate...i just know my logs are fine so I'm not worried.
 

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Discussion Starter · #12 ·
Here is what I've found and heard. Mind does it every once in a while (Gotboost kit on Cobb). I logged it and it won't happen under acceleration...only when cruising or idle or decel. I was told it's an air bubble that sometimes hits it on the return. The Cobb sampling rate is incredibly fast and as such it never misses a beat. I heard Cobb/Gotboost was looking at a slower sample rate to eliminate seeing these.

Who knows how much of the above is accurate...i just know my logs are fine so I'm not worried.
Ah.... Yea my logs look excellent as well so i didnt really bother. The only time it does pop up like that on the low side is during slow driving...
 

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Its possible that the sensor is send that reading out temporarily during a brief moment due to fuel cavitation at some point. We are actually just finishing testing on a few new features which would invalidate that reading and it would never be displayed on the ap unit. This will be out with out next software release and you will just need your tuner to update the map for you. You currently shouldn't see any ill effects from what you are describing, but no worries it will be fixed soon.
+1
 
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