e85 ethanol gas in 08 Pontiac Vibe

[robertfixit]

I am new here but I have several car stories you might find interesting. In this case, I switched to E85 gas in my 2008 Pontiac Vibe. Some of you may know that the Pontiac Vibe is basically a Toyota Matrix sold by Pontiac. It uses the same Toyota engine as a Corolla of similar year.

I did not have experience with E85 other than what I saw on youtube, people using it for tuning high horsepower cars because it is essentially a very high octane type of fuel.

A few years back, gas was almost $6 a gallon in California. I read a story about a guy in france who used E85 in his Toyota Yaris for over a year with no issues because in his country gas was $7 per liter. So I started experimenting with E85 since it was only a bit over $3 a gallon. I raised the mix of regular gas and E85 to about 35-40% before the computer could not keep up with it anymore.

I tried to figure out I could get more fuel into the engine. For those that do not know, E85 requires much more fuel to be injected than regular gas. I then realized that the higher performing 2ZZ engine had higher flowing injectors and would bolt right in.

I picked up a set from Amazon for only 50 bucks and put them in. To my surprise, it worked perfectly with the amount needed to run E85. In fact, it was still putting in too much fuel. The computer eventually compensated and I daily drove it this way for almost a year.

There is a myth that E85 will kill your fuel lines and fuel pump, but in fact that never happened. When I bought a newer car, I gave the car to my mom. I had intended to put the regular injectors back in, but never did. Combined we have driven 60,000 miles on straight E85 over the years and it still works fine.

I still intend to put the original injectors back in, because gas is now $4 a gallon. So the $3 a gallon E85 is no longer a savings, in fact it is costing more now because with E85 you get poop gas mileage. Sure you can fill up the whole car for $20, but it only lasts about a week.

The only issue I had is that because the injectors are a big too large, you have to let the car warm up for about a minute before driving. The computer can't compensate enough when it is stone cold.

Also, we did run into an issue where they ran out of gas because they went on some wild trip and couldn't find an E85 station. Someone gave them a gallon of gas but of course that did not work well. I had to go get 3 gallons of e85 and deliver it to them so they could drive it again.

So next time you read a story about e85 corroding out your car fuel lines and pump, just tell them that is maybe not true.

 

[GR_CoB]

I ran E15 in the same engine, no difference noticed in performance or fuel consumption, but $ savings were worth it at the time.

Interesting experiment on your end. So the computer adjusted to the E85 mix so much that now it can't run on regular E10 gasoline?

 

[ctechbob]

I ran E15 in the same engine, no difference noticed in performance or fuel consumption, but $ savings were worth it at the time.

Interesting experiment on your end. So the computer adjusted to the E85 mix so much that now it can't run on regular E10 gasoline?

More likely is is can't pull enough fuel out of it with the bigger injectors.

 

[melk]

Thanks for further confirmation that I would never want to run E85

 

[fantastic]

Well, the manufacturers know a bit more than this & they update more than "Fuel lines" to be compatible with e85. Unfortunately, this is equivalent to "My 65 year old neighbor hasn't died of smoking cigarettes yet so there must be no issues".

 

[kschachn]

Hopefully you won't have to fixit, Robert.

 

[thastinger]

I am new here but I have several car stories you might find interesting. In this case, I switched to E85 gas in my 2008 Pontiac Vibe. Some of you may know that the Pontiac Vibe is basically a Toyota Matrix sold by Pontiac. It uses the same Toyota engine as a Corolla of similar year.

I did not have experience with E85 other than what I saw on youtube, people using it for tuning high horsepower cars because it is essentially a very high octane type of fuel.

A few years back, gas was almost $6 a gallon in California. I read a story about a guy in france who used E85 in his Toyota Yaris for over a year with no issues because in his country gas was $7 per liter. So I started experimenting with E85 since it was only a bit over $3 a gallon. I raised the mix of regular gas and E85 to about 35-40% before the computer could not keep up with it anymore.

I tried to figure out I could get more fuel into the engine. For those that do not know, E85 requires much more fuel to be injected than regular gas. I then realized that the higher performing 2ZZ engine had higher flowing injectors and would bolt right in.

I picked up a set from Amazon for only 50 bucks and put them in. To my surprise, it worked perfectly with the amount needed to run E85. In fact, it was still putting in too much fuel. The computer eventually compensated and I daily drove it this way for almost a year.

There is a myth that E85 will kill your fuel lines and fuel pump, but in fact that never happened. When I bought a newer car, I gave the car to my mom. I had intended to put the regular injectors back in, but never did. Combined we have driven 60,000 miles on straight E85 over the years and it still works fine.

I still intend to put the original injectors back in, because gas is now $4 a gallon. So the $3 a gallon E85 is no longer a savings, in fact it is costing more now because with E85 you get poop gas mileage. Sure you can fill up the whole car for $20, but it only lasts about a week.

The only issue I had is that because the injectors are a big too large, you have to let the car warm up for about a minute before driving. The computer can't compensate enough when it is stone cold.

Also, we did run into an issue where they ran out of gas because they went on some wild trip and couldn't find an E85 station. Someone gave them a gallon of gas but of course that did not work well. I had to go get 3 gallons of e85 and deliver it to them so they could drive it again.

So next time you read a story about e85 corroding out your car fuel lines and pump, just tell them that is maybe not true.

Were you ever able to datalog any of the engine management parameters to see what was actually happening with fueling? I.E. STFT, LTFT, adaptive learning etc.
Did you ever test the Ethanol % of the final fuel mix you ran?

 

[AdmiralYoda]

I'm guessing that since E85 has been available most modern cars have the hardware to accept it...except for the ethanol sensor and associated wiring/computer programming. It detects the ratio of ethanol to gasoline and the computer can compensate based on that percentage.

I doubt the manufacturers had different fuel lines, hoses, filters, pumps, etc. for vehicles that were capable of running on E85. It would just be easier/cheaper to use all common parts.

I suspect it is the sensor, computer, injectors and associated wiring that makes a car E85 capable.

 

[robertfixit]

Were you ever able to datalog any of the engine management parameters to see what was actually happening with fueling? I.E. STFT, LTFT, adaptive learning etc.
Did you ever test the Ethanol % of the final fuel mix you ran?

The overal fuel trims came out to a less than -10% long term trim across the board. The injectors matched what it needed.

But the first start in the cold (I assume) does not compensate the same. During the day it is fine, it is only if its really cold out the OEM ECU adds extra fuel and it does not like that.

So I should say that if you live in a cold climate, definitely would be a problem.

 

[robertfixit]

I ran E15 in the same engine, no difference noticed in performance or fuel consumption, but $ savings were worth it at the time.

Interesting experiment on your end. So the computer adjusted to the E85 mix so much that now it can't run on regular E10 gasoline?

In a pinch I could put a gallon or 2 of regular gas. But if you were to say just fill it up with regular gas it would start but not be very drive worthy. Too much fuel with the bigger injectors.

 

[LDM]

If you put in larger injectors you need to adjust the parameters for the tune in the PCM. While it has some ability to compensate, not properly tuning the vehicle makes for all sorts of issues. The pulse width of the injectors as well as the total flow parameters are very important for proper engine operation.

Also, the whole E85 won't damage your fuel lines thing is entirely dependent on the vehicle. Unless the vehicle is newer and has flex fuel compatible parts, E85 can absolutely cause damage to the fuel system over time. While many new vehicles do have flex fuel compatible fuel lines and systems even if they are not actually flex fuel listed, many older vehicles do not. You need to check your vehicle to determine if the fuel system is capable of handling E85 if you want to do a conversion to use it.

I run E85 in my 2018 Sierra 6.2L as I can get it cheaply around my area. Cost me $50 for the ethanol sensor and I enabled the E85 parameters in the tune. For whatever reason, GM never made a 6.2L flex fuel, only the 4.3L and 5.3L got the flex fuel for some reason. But the fuel lines and system are 100% compatible with E85 as they are the same across all the trucks.