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Jonny Energy

Time to convert!

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Going thru old threads and found your install thread.  My 09 Cobalt has a factory instant and average mpg that is pretty accurate regardless of E blend, I have to believe the Jonnyenergy kit will throw that off by a set percent all the time.  Agree/disagree? 

 

Not that it's a problem but something to be aware of cause I think the factory gauge is going to lie to me, or anyone else using it to claim no or very small loss in fuel economy.

 

When using the Scangage which used airflow to calculate fuel used, it has to be calibrated to a certain blend to be accurate.   

 

David

Edited by roosterk

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Going thru old threads and found your install thread.  My 09 Cobalt has a factory instant and average mpg that is pretty accurate regardless of E blend, I have to believe the Jonnyenergy kit will throw that off by a set percent all the time.  Agree/disagree? 

 

Not that it's a problem but something to be aware of cause I think the factory gauge is going to lie to me, or anyone else using it to claim no or very small loss in fuel economy.

 

When using the Scangage which used airflow to calculate fuel used, it has to be calibrated to a certain blend to be accurate.   

 

David

 

I find my vehicle reads approximately the same as on gas, while the scangauge of course reads E85 mileage.

 

When you input gallons of fuel when you fill, that calibrates the scangauge. It's always as accurate as your last fill. ;)

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My question to you:  how high of an ethanol blend have you put into your vehicle?  

With the Cobalt been running E40 for last month or 2,  get to close to 0 and get a CEL, but did have it light up tonight.   Haven't taken the time to learn the xguages to see long term trim.   Also have 2010 impala FFV so it get e85 most of the time, dodge stratus and nissan altima generally go 50/50 when I fill them for my girls.  Never a CEL on the Stratus, always a CEL on the altima(emission leak) 

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I find my vehicle reads approximately the same as on gas, while the scangauge of course reads E85 mileage.

 

When you input gallons of fuel when you fill, that calibrates the scangauge. It's always as accurate as your last fill. ;)

By same in gas, you mean it's lieing to you.  that's what I expect.   I used the scanguage more with my other cars than with the fairly new to me Cobalt, changing from E0 to E10 to Ewhatever blend I made that day it's not accurate, and neither is my blending.  

 

I guess/expect the factory guage to be consistant as it's working off injector pulse vs scanguage's airflow to fuel via 14:1.  Even though JE kit adds a 25%(guess) 2nd pulse of the first.  So today when I got 40 mpg with E40 via factory guage, with JE extra pulse adding 25%(guess) more fuel with the same blend the factory guage would actually say I'm getting 50 mpg cause it doesn't know that 2nd pulse happened.    If in the JE standard setting at 29% 2nd pulse (guess based on energy contend) then factory MPG wouldn't change or atleast be pretty close to E0 or E10.

 

IMO once the car goes closed loop it doesn't matter what number the kit is set to, the O2 & MAF takes over, but hammer it to get it to go open loop, I'm not sure what happen, I think it uses open loop map plus Long term fuel trims,  if it didn't why have long term fuel trims.  JE kit cheats to keep LTFT's with a lower density fuel within the ECU's normal range. 

 

Dang, ment in previous post when I get close to 50%E with the cobalt, not 0, but can fix it.

Edited by roosterk

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By same in gas, you mean it's lieing to you.  that's what I expect.

 

Yes, my vehicle's mpg gauge reads about 4.5 mpg higher than the scangauge, and very close to what I get on E10. I suspect if it was flex, it might be more accurate. The difference is because I have a conversion installed.

Edited by TD

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If I am not mistaken, the E85 kits feature a "cold start" function in which the mixture is made more rich for the first(?) minute in order to enhance starting and making the % "assumption" not totally correct.    Then there is the issue of return fuel line from the injectors which can also effect the % assumption.

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This is probably as good a time as any to clear up some hardware questions about conversion kits that have confused me for some time. I've heard a few people talk about conversion kits, and I had some say that they wish they could use E85, but their vehicle isn't flex fuel.

 

As we all know, flex fuel vehicles have metal fuel lines, a special powertrain, and are equipped to handle higher blends of ethanol like conventional vehicles aren't. But even with the conversion kit on, wouldn't high blends of ethanol still risk damage on the fuel lines and the powertrain (now I feel like one of those haters, but one has to be prepared)? How exactly do the kits make a conventional vehicle capable of handling high blends like E70-E85 without significant damage?

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Conversions simply connect between the injectors and the engine. (Unplug each injector and connect the conversion connectors between the wires.) They often also have a ground wire you need to connect to the vehicle.

 

All the conversion does is increase the length of the electrical pulse sent to the injectors so it injects more fuel. They often also have an even longer pulse with a cold start. This can be via control by a temperature sensor, although some conversions do this on every start, whether cold or warm. I have one of each.

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