E85 Conversion Questions
Jun 17, 2016 | 12:17 PM
#11
Thread Starter
TECH Enthusiast
Joined: Nov 2015
Posts: 536
Likes: 7
Because calibrating seamlessly between two different fuels is more difficult than calibrating for one fuel. If every vehicle that could run ethanol did, customer complaints would inevitably be higher. Historically, domestic manufacturers have only sold enough flex fuel capable vehicles to meet requirements to receive EPA emissions credits.
e85 is all around me, but i was afraid that if i did an e85 tune and found myself where there wasn't any e85 ( I travel a lot) if I could still use the base tables to put unleaded in so i wouldn't be stranded somewhere in BFE
as far as i know, the flex fuel vehicles that were in production around that time could use both fuels, so i was going to duplicate that.
Jun 18, 2016 | 09:25 PM
#15
You can wire in the sensor to do the conversion.
My understanding is that you need to use an actual Flex fuel calibration as there maybe missing tables not shown by most tuning software to fully enable the function and have it work correctly. Some have reported needing to use a factory flex fuel calibration in order to get it to function properly.
I know the fuel rails are stainless Vs plastic.
I am not sure if the lines themselves are different or if it just has an adapter on it.
The injectors are a high rating PSI 34 Vs the 24 and use an Ev6 connector Vs the multec. connector.
The fuel fill neck has a special coating on it.
My understanding is that you need to use an actual Flex fuel calibration as there maybe missing tables not shown by most tuning software to fully enable the function and have it work correctly. Some have reported needing to use a factory flex fuel calibration in order to get it to function properly.
I know the fuel rails are stainless Vs plastic.
I am not sure if the lines themselves are different or if it just has an adapter on it.
The injectors are a high rating PSI 34 Vs the 24 and use an Ev6 connector Vs the multec. connector.
The fuel fill neck has a special coating on it.
Jun 19, 2016 | 08:44 AM
#16
I received a PM about this, and figured I would post up here in case people were searching. 1FastBrick is pretty much dead on as far as converting a vehicle.
I use EFI Live, but I am sure it is very similar with HPTuners.
Get a flex fuel tune, and do a segment swap over your original tune. I am running a 6.0, so this is where I copied some stuff from my previous tune that I had in my truck. Copy engine size, Main VE table, spark tables, etc, copy your tables to your new tune and flash that to your vehicle.
You will need a fuel composition sensor and pigtail. I used 13577429 that I got off ebay for about $45.
I did away with my MAF so I just used that 5v reference to run power to my sensor. The sensor will need a ground, 5v reference, and a wire going to the PCM that will now have to be ran to pin 56 of the blue connector.
It is not necessary to change to a return fuel system, but lets face it, if you are swapping to e85 for power, you could be needing it.
When the vehicle is running see if you are showing an ethanol percentage by logging. My truck for some reason will not adjust the percentage until I am driving a little (I think it has to do with the RPM's being up, but haven't messed with it because it really doesn't bother me). Your ethanol content should be around 10% if you have pump gas in it. If your tune has been nailed down, and you were running the proper commanded AFR for 10% ethanol in your previous tune, it should be perfect.
As 1FastBrick says, make sure your system is compatible for flex fuel. If so, you can add E85. Now see if you are able to log ethanol content again and see if the number changes. I get about mid 70's for ethanol content with E85 around here. I am not sure if my sensor is 100% correct as I was off slightly for my fuel trims. I had to adjust the stoich ratio commanded for E85 slightly. I had to do this to nail my tune back down when I was running full e85. I didn't change the ratio at 10%, I changed it at 75% where my new fuel was at. When I got the stoich ratio so that my tune was nailed down again with the higher ethanol content, I made the stoich ratio a straight line from 0 to 100% ethanol. I can put pump gas, e85, or any mixture of the two in my truck and it is dead on. I will be doing this to my Chevelle too when I get some time.
I can see if I have tune files for EFI Live and HPT and post them is anyone is interested.
I use EFI Live, but I am sure it is very similar with HPTuners.
Get a flex fuel tune, and do a segment swap over your original tune. I am running a 6.0, so this is where I copied some stuff from my previous tune that I had in my truck. Copy engine size, Main VE table, spark tables, etc, copy your tables to your new tune and flash that to your vehicle.
You will need a fuel composition sensor and pigtail. I used 13577429 that I got off ebay for about $45.
I did away with my MAF so I just used that 5v reference to run power to my sensor. The sensor will need a ground, 5v reference, and a wire going to the PCM that will now have to be ran to pin 56 of the blue connector.
It is not necessary to change to a return fuel system, but lets face it, if you are swapping to e85 for power, you could be needing it.
When the vehicle is running see if you are showing an ethanol percentage by logging. My truck for some reason will not adjust the percentage until I am driving a little (I think it has to do with the RPM's being up, but haven't messed with it because it really doesn't bother me). Your ethanol content should be around 10% if you have pump gas in it. If your tune has been nailed down, and you were running the proper commanded AFR for 10% ethanol in your previous tune, it should be perfect.
As 1FastBrick says, make sure your system is compatible for flex fuel. If so, you can add E85. Now see if you are able to log ethanol content again and see if the number changes. I get about mid 70's for ethanol content with E85 around here. I am not sure if my sensor is 100% correct as I was off slightly for my fuel trims. I had to adjust the stoich ratio commanded for E85 slightly. I had to do this to nail my tune back down when I was running full e85. I didn't change the ratio at 10%, I changed it at 75% where my new fuel was at. When I got the stoich ratio so that my tune was nailed down again with the higher ethanol content, I made the stoich ratio a straight line from 0 to 100% ethanol. I can put pump gas, e85, or any mixture of the two in my truck and it is dead on. I will be doing this to my Chevelle too when I get some time.
I can see if I have tune files for EFI Live and HPT and post them is anyone is interested.
Jun 20, 2016 | 04:53 PM
#17
Thread Starter
TECH Enthusiast
Joined: Nov 2015
Posts: 536
Likes: 7
I noticed in some 06 vehicles they didn't use the fuel sensor. They did a virtual flex fuel sensor.
Virtual fuel sensor for E85 flexible fuel (L59)
Light duty GM trucks equipped with the flexible fuel-capable L59 version of the Vortec 5300 use a new virtual fuel sensor, replacing their previous physical fuel sensor, for improved quality, reliability and dependability and increased customer value.
Essentially, control for the fuel sensor has up-integrated into the Powertrain Control Module (PCM). Based on input readings primarily from the O² (oxygen) sensor, fuel level sensor and vehicle speed sensors and using a new algorithm, the PCM adjusts the length of time the fuel injectors are open (duration) to adjust fuel control in accordance with the different compositions of the fuel being used. "
Would that be something I could segment swap?
Virtual fuel sensor for E85 flexible fuel (L59)
Light duty GM trucks equipped with the flexible fuel-capable L59 version of the Vortec 5300 use a new virtual fuel sensor, replacing their previous physical fuel sensor, for improved quality, reliability and dependability and increased customer value.
Essentially, control for the fuel sensor has up-integrated into the Powertrain Control Module (PCM). Based on input readings primarily from the O² (oxygen) sensor, fuel level sensor and vehicle speed sensors and using a new algorithm, the PCM adjusts the length of time the fuel injectors are open (duration) to adjust fuel control in accordance with the different compositions of the fuel being used. "
Would that be something I could segment swap?
Jun 20, 2016 | 05:10 PM
#18
I noticed in some 06 vehicles they didn't use the fuel sensor. They did a virtual flex fuel sensor.
Virtual fuel sensor for E85 flexible fuel (L59)
Light duty GM trucks equipped with the flexible fuel-capable L59 version of the Vortec 5300 use a new virtual fuel sensor, replacing their previous physical fuel sensor, for improved quality, reliability and dependability and increased customer value.
Essentially, control for the fuel sensor has up-integrated into the Powertrain Control Module (PCM). Based on input readings primarily from the O² (oxygen) sensor, fuel level sensor and vehicle speed sensors and using a new algorithm, the PCM adjusts the length of time the fuel injectors are open (duration) to adjust fuel control in accordance with the different compositions of the fuel being used. "
Would that be something I could segment swap?
Virtual fuel sensor for E85 flexible fuel (L59)
Light duty GM trucks equipped with the flexible fuel-capable L59 version of the Vortec 5300 use a new virtual fuel sensor, replacing their previous physical fuel sensor, for improved quality, reliability and dependability and increased customer value.
Essentially, control for the fuel sensor has up-integrated into the Powertrain Control Module (PCM). Based on input readings primarily from the O² (oxygen) sensor, fuel level sensor and vehicle speed sensors and using a new algorithm, the PCM adjusts the length of time the fuel injectors are open (duration) to adjust fuel control in accordance with the different compositions of the fuel being used. "
Would that be something I could segment swap?
Jan 31, 2017 | 02:18 PM
#20
Teching In
Joined: Nov 2014
Posts: 12
Likes: 0
From: Michigan
I've been looking into this a lot lately and found some threads on other forums
that may or may not help you, but I'll post it for other people.
Gen III Flex fuel Write-up - LS1TECH
And I will attach a 02 Flex Fuel Tahoe OS file below for anyone that has a return
style fuel system and wants to look at how the computer manages ethanol when
it's in the fuel system.
that may or may not help you, but I'll post it for other people.
Gen III Flex fuel Write-up - LS1TECH
And I will attach a 02 Flex Fuel Tahoe OS file below for anyone that has a return
style fuel system and wants to look at how the computer manages ethanol when
it's in the fuel system.
