Monday, October 24, 2016

The sweet spot

Putting 4 gallons of E85 in right when the gas light comes on results in about 35% ethanol, and almost 93 octane.  It's about a $7.50 per tank savings, and doesn't really lost much in the way of mileage.  This is the ethanol sweet spot.

If E30 were more widely available at blender pumps, it would be very compelling for cars that require premium fuel.  It would be a nice savings.

Tank #26

I got a CEL a little before halfway through the last tank, and it cleared in about 50 miles or so.  Stayed off for the rest of the tank.

I decreased the amount of ethanol in this tank as a result.  I think 4 gallons of E85 per tank is the sweet spot, the most that can be used without risking a check engine light.  I put a little more than that in this tank.

I got about 269 miles before the low gas light came on, about 11 miles less than the all gasoline tank.  That's a trivial loss in mileage.

gallons e85: 4.182 @ $1.559/ gallon

gallons 87 octane gasoline: 8.469 @ 1.859/ gallon

ethanol content of tank: 36.27%

octane of tank: 92.988

savings per tank compared to premium @ $2.559/ gallon: $7.58

Wednesday, October 19, 2016

Tank #25

So the gas light came on at 280 miles on my all gasoline tank, not really any different that my high ethanol tanks.  Weird.  I did take an on-ramp quite aggressively when it came on, so maybe it would have done more under normal circumstances.

Anyway, the topic at hand:

gallons e85: 4.511 @ $1.649/ gallon
gallons of 87 octane gasoline: 8.161 @ $1.949/ gallon

ethanol content of tank: 36.64%
Octane of tank: 93.095

savings per tank compared to 93 octane @ $2.459/gallon: $7.82

No CEL so far.

Tuesday, October 11, 2016

Just gas!

I was in a hurry today, and one of the E85 pumps at Meijer had a busted gas dispenser, so I just filled up with 100% 87 octane gas.

The last tank was about 32% ethanol, with no CEL's.  I swear, any car in America can run E30, if it were commonly available.

I got about 280 miles on the last tank before the low fuel light came on.  I'll try and see when that happens with this tank, to get a feel for what the hit to mileage is from higher blends of ethanol.

Wednesday, October 5, 2016

Tank #24

Gallons E85: 4.013 @ $1.699/ gallon

Gallons 87 octane gas: 10.496 @ $1.999/ gallon

ethanol content of tank: 32.72%

octane of tank: 92.2

savings per tank compared to premium @ $2.499/ gallon: $8.54

The CEL went off shortly after I refilled.


So on this tank, the CEL went on shortly after refilling, was on for most of the tank, went off about 3/4 into the tank, and turned back on right before I refueled.

Monday, September 26, 2016

10,000 miles on ethanol blends

So it's been 10,000 miles since I started this experiment of mixing E85 with straight 87 octane gasoline (E10, really) to make a higher ethanol content blend.  I've averaged about E30 during this time, going as high as E40.  I have not had one drivability or reliability issue.  Not one.

Again, this car is a 2004 Acura TL with 150k miles on it to start.  It is not a flex fuel vehicle, not specifically designed for high ethanol blends.

There is a lot of misinformation on the 'net about what E85 does to non-flex fuel cars.  Let this blog be evidence that modern cars can easily handle higher ethanol blends (E15, E20, E30), if not straight E85.  By modern cars, I mean everything after, say, 2001.

Considering that the average car is 11 years old, we are rapidly moving to a vehicle fleet that could handle a lot more ethanol in the fuel than is currently available.  If more retailers had E85 and blender pumps, and if the blends were priced fairly, a lot more ethanol could be sold in fuels than is currently the case.