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Posted
3 minutes ago, RDKILL said:

Sorry to inform you, but your hypothetical analysis is incorrect.

My truck is tuned to run a 50/50 mix, and if I choose to, I can run 100% 93oct and not have any problems...I just can't run 100% E85.

I run 93 only during the cold winter months without a problem, so no biggie other than loss of performance if there's no E85 available.

This is factual and true data.

Have you run 100% 93 yet?

Posted
9 hours ago, KARNUT said:


I don’t understand your response. My GMC was E-85, ran well on all gas. The best on E-85. If I was going to run an engine tune I would run a E-85 tune. Running a tune for a mix of 93 gas mixed with E -85 would be a lesser tune for lower octane versus an E-85 tune. With the sensor you would get more hp out of E-85. You still could run other grades with self adjustment.


Sent from my iPhone using Tapatalk

Now this may be the difference between a tune and a sensor.

I think with a sensor I would be able to run 100% E85 if I wanted to...just need to confirm if I would be able to do 93 also, which I can't see why not, but better to verify first.

I could use an additional 25 ponies.

Posted
1 minute ago, Nasty said:

Have you run 100% 93 yet?

LOL!

You need to read my post a little closer...I run 93 only in the cold winter months, so yes I have with no problems.

  • 2 months later...
Posted

I have a 2015 Silverado LT 4x4 Double Cab 5.3 with RPO code FH0 (Not Flex Fuel).  I have been running E85 in my truck for the last 4 tanks with absolutely ZERO problems.  No check engine light, no stuttering, no hesitations, no misfires on cold starts.  I am beginning to believe this $100 option is for a yellow gas cap?  It wouldn't surprise me a bit, and I'm going to continue to run E85 till winter hits.  I can definitely tell those extra 25 ponies are behind the wheel!!!!!!!

  • Like 1
Posted
4 hours ago, nkoenig said:

I have a 2015 Silverado LT 4x4 Double Cab 5.3 with RPO code FH0 (Not Flex Fuel).  I have been running E85 in my truck for the last 4 tanks with absolutely ZERO problems.  No check engine light, no stuttering, no hesitations, no misfires on cold starts.  I am beginning to believe this $100 option is for a yellow gas cap?  It wouldn't surprise me a bit, and I'm going to continue to run E85 till winter hits.  I can definitely tell those extra 25 ponies are behind the wheel!!!!!!!

The only problem you might run into is a lean code if you run 100% all the time and really get on the throttle.  The ECU does not accommodate for the ethanol in the system since it can't detect it and so will not change you fuel map to do so.  The kit is well worth it  and the tune will really wake up the truck. To me it is well worth the cost and I'm going to convert our 16 Suburban over to E85. 

 

Not to mention E85 here is $2.16 a gallon and premium is $3.26.  So even with the lower mpg I get I'm still ahead on miles per gallon cost.

Posted

So far so good. My mpg has minimally suffered, but in return I have lots more power.  All I’m saying is, the now $300 conversion (instead of the $100 option) might not be necessary. I will return to running 87 during the cold months. 

Posted
3 hours ago, nkoenig said:

So far so good. My mpg has minimally suffered, but in return I have lots more power.  All I’m saying is, the now $300 conversion (instead of the $100 option) might not be necessary. I will return to running 87 during the cold months. 

What did you do?

Did you get an E85 tune and/or a sensor, or just a tune?

On another note:

I did the CRC GDI intake valve cleaner and boy what a difference it made!

  • Like 1
Posted
11 minutes ago, RDKILL said:

What did you do?

Did you get an E85 tune and/or a sensor, or just a tune?

On another note:

I did the CRC GDI intake valve cleaner and boy what a difference it made!

You have to have a sensor to get the full benefits of running E85.  Otherwise the ECU has no way of knowing what fuel you are running to make changes to the fuel map.

  • Like 1
Posted
16 minutes ago, Black02Silverado said:

You have to have a sensor to get the full benefits of running E85.  Otherwise the ECU has no way of knowing what fuel you are running to make changes to the fuel map.

Thank you, I realize that is the case, but was just wondering what nkoenig did being that he mentioned the kit may not be needed.

I have seen performance increase with just a tune, but I am thinking of getting in touch with CJ to explore the kit.

BBP has told me that would be the best way to take full advantage of the fuel...just like if I added headers, cam, supercharger etc.

Posted
27 minutes ago, RDKILL said:

Thank you, I realize that is the case, but was just wondering what nkoenig did being that he mentioned the kit may not be needed.

I have seen performance increase with just a tune, but I am thinking of getting in touch with CJ to explore the kit.

BBP has told me that would be the best way to take full advantage of the fuel...just like if I added headers, cam, supercharger etc.

He didnt do anything but put e85 fuel in his tank

Posted
On 4/12/2016 at 9:07 AM, bobbobtar said:

Seat of the pants, I could tell it was different, felt like it had better acceleration.

Better acceleration, better tranny shifting, no black soot on or in tailpipe.

And a moonshine smell whipe running all make up for the mpg loss! :thumbs:

  • Like 1
Posted
9 hours ago, RDKILL said:

What did you do?

Did you get an E85 tune and/or a sensor, or just a tune?

On another note:

I did the CRC GDI intake valve cleaner and boy what a difference it made!

I didn’t get an e85 tune. Everything is still the way it came from the factory. 

Posted

Looking under my truck just forward of the fuel tank, I see two metal fuel tubes coming/going to the fuel tank.

I'm not sure which tube is going in and which is going out.

 

Does anyone know for sure which tube the sensor would be grafted/installed to?

I see the wire harness is tied up near the tubing, so I'm assuming this is the area the sensor would be installed, just not sure which tube...hate to cut the wrong one!

  • 1 month later...
Posted

I see in the pcm that mine auto detects for the sensor. I can change the tune in there. It is sad that the fuel line to the engine is so much work to replace. A splice in sensor is easier but cost much more and not for the average Joe as a DIY. 

I will look into the software but so far I don't see or believe the MPG changes based on alcohol sensor. Meaning it takes much more E85 to run then gasoline. So how is it calculating this?   

Screen Shot 2018-10-05 at 3.29.11 PM.png

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