Flex Fuel

[Don P]

So come to find out my little Ranger is a flex fuel vehicle. This means it has alcohol heads and computer whizzbangs to run the engine on a wide range of moonshine/gas blends. There is a sensor under my seat on the frame rail that determines the alcohol content and fuel temparature and sends it to the computer which adjusts timing and injection, through big bore injectors for that engine size.

I've never run anything but E10 and a tankful or few of better gas. The timing went out of sight advanced recently and there is no turning the distributor on these, its all pickups and computer. I suspected that fuel composition sensor had failed, and being good corporate folks it fails to "I'm running on E85". I found some flex fuel the other day and got a tankful. That fixed it, the timing and fuel blend now match. I can floor it in the wrong gear up a hill, no pinging, and this stuff seems to "burn" more like diesel, it has depth. I have half a tank of experience but it seems to be interesting stuff. The computer is lighting it waaay early, the burn time is tremendous compared to gas. It seems to have some of the depth of diesel compared to gas... or I'm imagining it after driving a sick truck.

That sensor is $750, the flex fuel was $3.44 and 45 minutes away each way so killer price but no go and I understand the mileage sucks, it is burning big gulps of mostly alcohol. But as fuel goes, it seems kind of badash. Climbing the hill out of the New valley I left a Topaz that was running up my rear  :D.

[LeeB]

According to the VIN on my 2019 Silverado, it will burn E85 also. Have not tried it. I wondered about the milage. Alcohol has about 27% less btu than gasoline. The price difference in the two at the pump may make up for it.

[barbender]

The last time we saw $4-$5 gas, I decided to try a tank of E85 in our flex fuel Dodge Caravan. It ran fine, except it didn't want to idle. It was about the sane cost per mile, but after 2 tanks and the idling issue didn't clear up I quit using it.  

[hedgerow]

Don P  I have a F-150 and a F-350 both flex trucks. We grow corn so we like E around here. E-85 around here not so easy to get. I haven't ran the numbers pre mile since this last huge jump up in price but a few years ago before Covid I ran E-85 a while. Both trucks adjusted to it fine but at the end of the day the cost per mile was higher to run the E-85. I run E-10 all the time in them and when I did a cost per mile on E-10 to non E the E-10 won out. E-15 is starting to show up around here some and some stations have what they call blender pumps so you can get like E-10 all the way up to E-85. I do use non E in all my small engines and chain saws. 

[Don P]

Well it towed the trailer with around 300 bf of wood on it a minute ago. Last trip home with it empty I was backing out of the throttle and downshifting hoping to get it home without blowing a piston, so this was a big difference. If it were more available I would probably just switch to running E85. As it is I've soldered together a fooler circuit that should give a ~60 hz signal that equates to E10 and sends the signal every 5 milliseconds which should equate to ~90 degree fuel temp. I'll run this tankfull out, switch back to E10 and confirm it is running poorly and then plug in the fooler to see if it will tell the computer I'm running on E10 no matter what is in the tank.



 

[kantuckid]

Based on info I've read previous to current energy situation, most vehicles cost more to run on flex, i.e. 15% ethanol, than regular 10% with adjustments for typical price points. My F-150, 5.0 V-8 and my turbo V-6 Lincoln Nautilus both ate flex engines. I did try a 50/50 combo of 15% flex and 10% 87 octane in FL last winter when this idiocy on fuel prices began as I was in LALA land area where fuel was insane on it's own. Engine ran same as always on 50/50 mix from same pump as it were. Truck calculates mpg on the run but was off the math as wasn't towing and it takes some miles to change from towing mpg to non towing, but it seemed the same distance wise. 
The corn I grow is going in the ground today and won't run my vehicles, but tastes better than field corn. Our latest favorite is called "Incredible".
 Corn gas makes energy from fertilizer made from fossil fuels, go figure on that one?  :D
 It was in discussion in 1973 when I went back to college and still is, well, sort of... : 

[Bert]

I've tried it in a Ford Expedition. I wont do it again. Truck ran fine but gas mileage was horrible.

[moodnacreek]

Don, did the topaz have N.Y. tags?

[Don P]

It had more of that local in a hurry home for dinner look :D.
I'm easing it down slow, it has a tank of premium in it as of this morning... in other words I need to do a little more soldering and then cast the board in epoxy. Even though it should be waterproof I think I'll drill a hole or look for a plug under the seat and just drop the wires through the floorboard down to the sensor and plugin. I've got no idea if it'll work, but the parts were cheaper by the dozen, I've got a few tries  :D. 

[Don P]

 I didn't think real hard when I poured a huge mass of epoxy on the circuit board, it got HOT.

I googled and made a quick and dirty oscilloscope with the arduino. No scale or much precision but it looks like it has a heartbeat in the correct order anyway.