I have a '95 Thunderbird which I had been driving for work as the CVT in my Insight puked and so my miserly friend was out of commission for a few months. I had been interested in E85 and had toyed with the idea of converting the car to run on it anyway (anyone building a street rod or high performance machine or any old muscle car should consider it).
While it was fun to get back into the saddle with some good ol' fashioned V-8 muscle under the hood, filling up at 19 MG with gas at 2.59(at that time) was not so fun. E-85 was 1.89 and having studied using ethanol as a fuel for a science project back in high school, I knew it wouldn't take too much to convert it. I read a paper from the Mankato University and seeing that they were able to test the Prius without any modifications, I decided to try a tank.
I got a check engine light (which I was fully expecting) and it idled a little rougher, but it ran quite well on it and had noticeably more power. In doing my research, I had found that alcohol is more corrosive than gasoline and certain types were more corrosive than others. Methanol and Ethanol were the two main alcohols used as fuel when I was researching this primarily because they have the highest energy density of the alcohols. I also had taken some classes in fuel injection and emission controls and alcohol was mentioned in discussion of fuel line anti-freeze (Heet).
Methanol (the kind in the old yellow bottles of Heet) should not be used in any vehicle with a catalytic converter, it can peel the lining of the fuel tank if you have a steel tank and it corrodes fuel system parts. Ethanol is not as bad, but it can eat certain things, most notably aluminum, so you don't want to use it on a vehicle with an aluminum fuel rail.
Aside from fuel system component issues, the two main things that need to change to run alcohol effectively are spark timing and fuel flow. Alcohol burns slower than gasoline and has a higher octane rating (ie, it is harder to light) so to compensate, ignition timing should be advanced approximately 20-30 degrees. E85 has a minumum of 15% gasoline (it varies from 15% in the summer to up to 30% in the winter) which helps E85 ignite and burn faster so it will run ok even without a timing change.
The second part of the equation, fuel flow, is easily changed in a carbureted car and is constantly adjusted in a fuel injected car. Alcohol has about 30% fewer BTU's of energy output per gallon than gasoline does and therefore requires more fuel to do the same amount of work. In order for an engine to run properly on E-85, fuel flow needs to be increased by 25-30%. The Prius testing that Mankato did proved that the engine control computer was able to adjust the fuel flow to compensate for the difference in fuels.
With this in mind, I decided to try it out on my T-bird, which was quite up to the task. It ran on it well, other than the check engine light and I got 17 mpg on the E85. My next step was going to be to increase the fuel flow to get rid of the check engine light. There are a couple ways to accomplish this, you could boost fuel pressure or reprogram the computer to keep the injectors on longer.
Boosting fuel pressure can disrupt the spray pattern and is hard to judge the increase in flow. Reprogramming the computer requires special equipment and parts and a thorough knowledge of the process, plus, you may run into a situation where the injector at full on doesn't supply enough fuel. The best solution would be to add larger fuel injectors to accommodate the added flow. It came stock with 19 lb/hr injectors, changing to 24 lb/hr injectors would increase fuel flow by around 26% which is right around where we want it. This would allow us to get the fuel flow where it needs to be, or at least close enough that the computer can adjust it without triggering a check engine light.
I was just getting ready to order some injectors when the engine locked up on a trip to Fargo (timing chain let loose, totally unrelated to the fuel. it had 200,000 miles on it, go figure) so the car has been parked now for about a year, I figure it'll probably cost 800-1200 to fix, it has OHC and it's an interference engine, meaning if the timing chain breaks while it's running, you have catastrophic engine damage, ie bent valves, holes in pistons, and the like...
I need to drive for work so I took the old transmissin apart on the Insight and it was just as I suspected, a ball bearing had gone bad (probably a 50$ part if that), unfortunately it was part of the "intermediate plate assembly" (the metal link belt and pulley apparatus that actually does the CV part) and it is considered one $1500 part. I took it to a machine shop and pressed the bearing out and got the numbers off of it, but was unable to cross reference it or get another one, so i had to bite the bullet and buy a whole transmission.
After getting the car running, I decided to try running E-85 in it since it had worked ok in the other one. It ran ok other than the expected check engine light, a little rough at idle once again and a little sluggish when waking up from auto-stop. My workaround was to let off the brake as the cross traffic light was changing so it would be running for a couple seconds before I had to move. About half way through a tank, I noticed that my battery guage hadn't moved off of full. A few gratuitous full throttle bursts confirmed my suspicions that the IMA wasn't providing boost. I then remembered that I had read in another thread that someone had a similar problem - erratic or no IMA assist and it was resolved by replacing the o2 sensor and it was surmised that the 02 feedback system plays an active role in determining when IMA is engaged.
After my next tank of straight gasoline my boost returned and I readily decided that it kind of defeated the purpose of having a hybrid car to save a few cents a gallon on fuel if it negates the "hybrid" part. I think the major problem is that our Insights use a wide band 02 sensor which will read a wide range of mixtures from around 8-25 to 1, most cars use a standard 02 sensor which only senses a narrow band of mixtures right around the stoichiometric ratio 14.7 to 1. They basically turn off and on, oscillating as the mixture hovers around the ideal mix. Whereas our cars operate over a wider range of mixtures so it is more of a variable voltage output (think dimmer switch as opposed to a normal light switch).
I also burn E85 in my 2003 chevy venture van (which also is not a flex-fuel vehicle) and it runs just fine other than the expected check engine light. So, in short, I would not recommend burning E85 in your Insight, but it will run on it.
While it was fun to get back into the saddle with some good ol' fashioned V-8 muscle under the hood, filling up at 19 MG with gas at 2.59(at that time) was not so fun. E-85 was 1.89 and having studied using ethanol as a fuel for a science project back in high school, I knew it wouldn't take too much to convert it. I read a paper from the Mankato University and seeing that they were able to test the Prius without any modifications, I decided to try a tank.
I got a check engine light (which I was fully expecting) and it idled a little rougher, but it ran quite well on it and had noticeably more power. In doing my research, I had found that alcohol is more corrosive than gasoline and certain types were more corrosive than others. Methanol and Ethanol were the two main alcohols used as fuel when I was researching this primarily because they have the highest energy density of the alcohols. I also had taken some classes in fuel injection and emission controls and alcohol was mentioned in discussion of fuel line anti-freeze (Heet).
Methanol (the kind in the old yellow bottles of Heet) should not be used in any vehicle with a catalytic converter, it can peel the lining of the fuel tank if you have a steel tank and it corrodes fuel system parts. Ethanol is not as bad, but it can eat certain things, most notably aluminum, so you don't want to use it on a vehicle with an aluminum fuel rail.
Aside from fuel system component issues, the two main things that need to change to run alcohol effectively are spark timing and fuel flow. Alcohol burns slower than gasoline and has a higher octane rating (ie, it is harder to light) so to compensate, ignition timing should be advanced approximately 20-30 degrees. E85 has a minumum of 15% gasoline (it varies from 15% in the summer to up to 30% in the winter) which helps E85 ignite and burn faster so it will run ok even without a timing change.
The second part of the equation, fuel flow, is easily changed in a carbureted car and is constantly adjusted in a fuel injected car. Alcohol has about 30% fewer BTU's of energy output per gallon than gasoline does and therefore requires more fuel to do the same amount of work. In order for an engine to run properly on E-85, fuel flow needs to be increased by 25-30%. The Prius testing that Mankato did proved that the engine control computer was able to adjust the fuel flow to compensate for the difference in fuels.
With this in mind, I decided to try it out on my T-bird, which was quite up to the task. It ran on it well, other than the check engine light and I got 17 mpg on the E85. My next step was going to be to increase the fuel flow to get rid of the check engine light. There are a couple ways to accomplish this, you could boost fuel pressure or reprogram the computer to keep the injectors on longer.
Boosting fuel pressure can disrupt the spray pattern and is hard to judge the increase in flow. Reprogramming the computer requires special equipment and parts and a thorough knowledge of the process, plus, you may run into a situation where the injector at full on doesn't supply enough fuel. The best solution would be to add larger fuel injectors to accommodate the added flow. It came stock with 19 lb/hr injectors, changing to 24 lb/hr injectors would increase fuel flow by around 26% which is right around where we want it. This would allow us to get the fuel flow where it needs to be, or at least close enough that the computer can adjust it without triggering a check engine light.
I was just getting ready to order some injectors when the engine locked up on a trip to Fargo (timing chain let loose, totally unrelated to the fuel. it had 200,000 miles on it, go figure) so the car has been parked now for about a year, I figure it'll probably cost 800-1200 to fix, it has OHC and it's an interference engine, meaning if the timing chain breaks while it's running, you have catastrophic engine damage, ie bent valves, holes in pistons, and the like...
I need to drive for work so I took the old transmissin apart on the Insight and it was just as I suspected, a ball bearing had gone bad (probably a 50$ part if that), unfortunately it was part of the "intermediate plate assembly" (the metal link belt and pulley apparatus that actually does the CV part) and it is considered one $1500 part. I took it to a machine shop and pressed the bearing out and got the numbers off of it, but was unable to cross reference it or get another one, so i had to bite the bullet and buy a whole transmission.
After getting the car running, I decided to try running E-85 in it since it had worked ok in the other one. It ran ok other than the expected check engine light, a little rough at idle once again and a little sluggish when waking up from auto-stop. My workaround was to let off the brake as the cross traffic light was changing so it would be running for a couple seconds before I had to move. About half way through a tank, I noticed that my battery guage hadn't moved off of full. A few gratuitous full throttle bursts confirmed my suspicions that the IMA wasn't providing boost. I then remembered that I had read in another thread that someone had a similar problem - erratic or no IMA assist and it was resolved by replacing the o2 sensor and it was surmised that the 02 feedback system plays an active role in determining when IMA is engaged.
After my next tank of straight gasoline my boost returned and I readily decided that it kind of defeated the purpose of having a hybrid car to save a few cents a gallon on fuel if it negates the "hybrid" part. I think the major problem is that our Insights use a wide band 02 sensor which will read a wide range of mixtures from around 8-25 to 1, most cars use a standard 02 sensor which only senses a narrow band of mixtures right around the stoichiometric ratio 14.7 to 1. They basically turn off and on, oscillating as the mixture hovers around the ideal mix. Whereas our cars operate over a wider range of mixtures so it is more of a variable voltage output (think dimmer switch as opposed to a normal light switch).
I also burn E85 in my 2003 chevy venture van (which also is not a flex-fuel vehicle) and it runs just fine other than the expected check engine light. So, in short, I would not recommend burning E85 in your Insight, but it will run on it.
