E85 towing

karatejosh

karatejosh

Well-Known Member
Joined
Apr 4, 2011
Location
raleigh
So I know E85 is the Devil lol but I have a 2014 tundra and I just filled up with it to see how it dose at 1.10 a gallon and a truck I drive in the city most the time and get 13 mpg it seems logical to atleast try it tuck has bumper to bumper for 110k and it will be long gone before then so not super concerned with long term affects but outside of my buddies that have it in race cars I don't know much about E85 not sure how it would perform towing but it sure would make trips to Harlan more affordable what do you guys think gas is cheap right now so it's not a super big deal but when it go's through the roof again it might be a great option or at least that's what I'm thinking
 
Hopefully you dont have the 5.7 if you do read up on the FFV motor issues.

You may start staring 6mpg down the barrel with no toyota support.
 
I read up and it seems that the problems are not related to actually putting E85 in it and sence I have 35k on mine hopefully I'm in the clear
 
I don't know much about the Tundra FFV problems, but for an engine designed for E85 or gas, the worst thing that happens is poor fuel economy because of the lower energy content and different stoichiometric ratio. Stoich for gas is 14.7:1, stoich for E85 (with actual 85%) is 9.7:1 so there's no way around a decently higher fuel consumption. The ethanol % range is pretty huge for E85 (the huge range is part of the E85 spec) so it will rarely actually be 85%. High octane is very nice though.
 
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Fabrik8 said:
I don't know much about the Tundra FFV problems, but for an engine designed for E85 or gas, the worst thing that happens is poor fuel economy because of the lower energy content and different stoichiometric ratio. Stoich for gas is 14.7:1, stoich for E85 (with actual 85%) is 9.7:1 so there's no way around a decently higher fuel consumption. The ethanol % range is pretty huge for E85 (the huge range is part of the E85 spec) so it will rarely actually be 85%. High octane is very nice though.
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Actually you would think that....

But Toyota in their infinite wisdom decided just building an E85 hardened engine wasnt enough. They went above and beyond with a way overcomplicated system that maximized the increased octane in the form of progressive electronic timing recurves and altered injection points.

Now all that results in an engine that gets damn near the same mpg on E85 as it does on regular old 87 octane.
A neat trick.

The bad you are probably wondering?

They didnt use a switch to activate this setting or give any operator input at all as a matter of fact. No they got high tech an installed an ethanol blend sensor system. Thats right your smart yota actually knows when you run E85 and does its magic. All that works pretty well. The problem kicks in because the sensor isnt really good. In fact it tends to get stuck in E85 mode quite frequently even when running regular pump gas. This results in predetination as the engine anticipates higher octane than its fed and as a result a marked drop in efficiency.

In extreme cases there are burned pistons. Toyota has been good about fixing those. But on the other end lots of Tundras are seeing 6-8 mpg unloaded and Toyota responds that it is normal.

The cure is to get a non FFV truck, it does not have the funky ethanol monitoring and progressive timing and fueling system.

That lack of feature cuts $225 off the sticker but commands a $4-5k premium in the used market.
NON FFV vehicles are not sold to SE Toyota dealers for some reason Toyota wont explain. My Tundra was brought to NC from Kentucky just to get a NON FFC engine.
 
As a side note, last time I filled up [regular], It was & still is app. $1.65. Mount Holly, Denver, & most of Charlotte. Drove through Dallas tonight, down 321 to I-85. Maybe a gas war, but all those stations are at $1.55!
 
Most of the cases I read about the sensor getting stuck the people said there truck had never had E85 in it it would have been really cool and probly alot esier if they just put a switch in rather then the sensor in the tank I wonder if someone will make a program that can allow you to change stuff probly not enough demand tho
 
rockcity said:
Ah damn, Toyota has problems just like the big 3. Who da thunk?
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Only difference is Toyota is much better about standing behind their vehicles and fixing problems. Sometimes even WAY out of warranty. Rust on your Ford, Chevy, or Dodge? Tough luck. Got a rusty Tacoma from 1998? Just take it back! (yes I know it is a 15 year 'rust' thing on the Tacomas but just had a guy tell me last week that is in the process of turning his 98' in for the rust recall). @dorton told me about a 3.0 V6 truck that got a new motor just a few years back. Under warranty.... It had never been fixed under warranty and only had ~125k miles on it.

I wonder what Ford would tell me if I called and said something about my 6.0 headgaskets? Same thing chevy or dodge would I imagine...
 
Ron said:
Actually you would think that....

But Toyota in their infinite wisdom decided just building an E85 hardened engine wasnt enough. They went above and beyond with a way overcomplicated system that maximized the increased octane in the form of progressive electronic timing recurves and altered injection points.

Now all that results in an engine that gets damn near the same mpg on E85 as it does on regular old 87 octane.
A neat trick.

The bad you are probably wondering?

They didnt use a switch to activate this setting or give any operator input at all as a matter of fact. No they got high tech an installed an ethanol blend sensor system. Thats right your smart yota actually knows when you run E85 and does its magic. All that works pretty well. The problem kicks in because the sensor isnt really good. In fact it tends to get stuck in E85 mode quite frequently even when running regular pump gas. This results in predetination as the engine anticipates higher octane than its fed and as a result a marked drop in efficiency.

In extreme cases there are burned pistons. Toyota has been good about fixing those. But on the other end lots of Tundras are seeing 6-8 mpg unloaded and Toyota responds that it is normal.

The cure is to get a non FFV truck, it does not have the funky ethanol monitoring and progressive timing and fueling system.

That lack of feature cuts $225 off the sticker but commands a $4-5k premium in the used market.
NON FFV vehicles are not sold to SE Toyota dealers for some reason Toyota wont explain. My Tundra was brought to NC from Kentucky just to get a NON FFC engine.
Click to expand...

Toyota doesn't sound like they're doing anything different than anyone else has been doing for at least a decade, it just sounds like they didn't implement it very well.

That's basically how all flex fuel engines are set up, they all use an ethanol content sensor. You have to have that because you need to compensate for anywhere from 100% gas to almost 100% ethanol, both because the tank will always have a mixture of the two, and because the ethanol content of E85 from the pump can vary so widely. Changing fuel mapping and ignition has to be done because of the combustion and energy differences, that's standard as well.
All modern cars adjust timing for octane, that's what wideband knock sensors are used for. Creeping up into the onset of knock is the way the game is played...

In practice the fuel economy is about 20% less usually, sometimes more depending on how good/bad your combustion efficiency and volumetric efficiency is to begin with. You'd have to be really aggressive with timing and run fairly lean to get the same power as gasoline and do even marginally better than that for fuel economy, especially if you're already starting out with E10 in most areas.
 
Fabrik8 said:
Toyota doesn't sound like they're doing anything different than anyone else has been doing for at least a decade, it just sounds like they didn't implement it very well.

That's basically how all flex fuel engines are set up, they all use an ethanol content sensor. You have to have that because you need to compensate for anywhere from 100% gas to almost 100% ethanol, both because the tank will always have a mixture of the two, and because the ethanol content of E85 from the pump can vary so widely. Changing fuel mapping and ignition has to be done because of the combustion and energy differences, that's standard as well.
All modern cars adjust timing for octane, that's what wideband knock sensors are used for. Creeping up into the onset of knock is the way the game is played...

In practice the fuel economy is about 20% less usually, sometimes more depending on how good/bad your combustion efficiency and volumetric efficiency is to begin with. You'd have to be really aggressive with timing and run fairly lean to get the same power as gasoline and do even marginally better than that for fuel economy, especially if you're already starting out with E10 in most areas.
Click to expand...
I was going to say the same thing. Except more snarky and without actual facts.
 
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