E85 in 2001 Civic DX - It works!
 

I want to share my experience getting my '01 civic DX to run E85. I've only taken the car out twice so it's still pretty fresh and I have a couple of tests to do that I would also like to share. I believe the method that I have used will prevent the car from running on gasoline, although I think a mixture of up to 4 gallons E10 gas and the balance (7 gal I think) of E85 will run.

The method I used involved installing injectors from an RSX-S of the same generation as the civic. I believe the stock injectors are 240 cc/min and the new ones are 310 cc/min. I was shooting for a 30% flow increase to account for the increased fuel requirements over gas needed to meet stoichiometric conditions. I got them off ebay last week for $66. They were shipped doused in carb cleaner, so my mailbox had a telling odor upon my arrival.

I had understood that the injectors would be a direct swap with the exception of having to use longer fuel rail mounting posts. The stock posts are M6X1.00 and I think the new ones need to be at least 35 mm long. I got 40 mm bolts to replace the posts, but they were a little too long. In the same trip to the hw store I managed to think ahead enough to get a 100 mm long piece of all thread. (I have to mention that I had to put everything back together the day before because I didn't have the posts. I didn't know what size to get!) I cut the all thread roughly in half with a hack saw and smoothed the cut ends down with a flat file. I observed how the threads on the factory end came together and worked my end to look the same. I slowly threaded the factory nut onto the cut edge and worked it back and forth until I was sure it would go on smooth when I went to do the install. I was pleased that it took much less time than other attempts during past projects. I got zinc coated all thread, so maybe I was remembering trying to do it on a stainless piece.

There is a spacer that holds the fuel rail at the correct height so that when you tighten its mounting nut it won't crush the injector. You have to use a larger spacer. I used the stock ones and a big nut. It made the spacer a little over twice as high. When I used the wrong size spacer the first time I put it together I over tightened the fuel rail mounting nut and broke off a small tab on the injector that serves the purpose of I think keeping the injector aligned radially and vertically. It's really small so I think it's just there as a mechanical reminder. I tried to make a new one and failed and now the car is running fine with no leaks without the tab. I inspected the position of the injector relative to the fuel rail, the head, and the injector mounting clip after I tightened the fuel rail down and it looked the same so I carried on.

When using the longer posts, and the longer injectors, the fuel rail doesn't slide into position very well. I put the rail and injector assembly in first, having put motor oil on the injector o-rings, and then held the spacers in place while I put the rail mounting bolt in from the top. I installed the factory edge of the bolt into the aluminum threads of the head below.

I also removed the air filter housing mounting rod that is attached to the head before installing the fuel rail to make space. To reinstall it required about 1/4" worth of washers. The same bolts worked fine, and the filter housing seems to fit fine on the throttle body. Getting those 10 mm bolts on and off would be a lot easier with a ratcheting wrench.

Prior to doing this swap I had run the car on up to 4 gal of E85 with the balance of the tank being E10. I think the tank holds about 11 gal. Above 4 gal I got an over lean MIL code. The stock ECU has a fuel trim parameter that can compensate for the increased fuel demand, but it only goes so far. I think +- 25% I think the way fuel trims work is they increase the injector duty cycle by the same factor across the entire fuel map. With the stock narrow band O2 sensor the ECU just looks for stoich A/F ratio and adjusts the trims until the condition is met. Using larger injectors sized to supply the increased fuel needs of E85 over gas puts more fuel through for the same duty cycle, and the ECU uses the fuel trim to fine tune your calculation.

I read and though about this a lot before doing it, and I'm sure I could have provided a bunch of links and not repeated writing what other people have done, but I wanted to put together the whole package in my specific experience in case anybody is trying to do something similar. Maybe somebody will save a trip to the hardware store.

I will measure the fuel economy, as well as the fuel trims and share them here. I was getting about 36 mpg driving fast, about 40 mpg driving slow. I have michelin hydro edge tires and full moon hub caps.

I just dump it in my non-FFVs. The CEL comes on, but I know why and I ignore it.

Sounds interesting. Subscribed to see results... also... to see what Frank Lee says next... hahahaha!

I know that when there's an "e85 cel" that it's near stoich or a bit lean... which I LIKE.

I should add, if you have cold winters like Minnesota, you will want to back off on the strength of the ethanol in your blend; it can lead to hard starting. But once going it's just fine. I wished I had the dual tank set-up from an awd Tempo to transplant into my fwd Tempo- one for e10 and one for e85 in the winter... both for e85 when it's not brutally cold. :thumbup:

P.S. Because e10 ONLY FOR COLD STARTING in winter; switch to e85 after a few minutes. e10 tank probably last all winter...

So you don't think running too lean is hard on the engine? I thought it would go high enough to start burning things or just be weak. I got the code at 4gal, so I didn't want to push it.

I don't understand why you want to run e85. I thought it was kinda a wash in terms of fuel economy and emissions. Here is a reference: E85 vs. Gasoline Comparison Test (The article actually argues e85 is more epensive over all.)

I just paid 2.59 for e85. E10 is same at that station, 2.39 elsewhere. I do it cause you can drink ethanol and it's renewable. It also can go at higher compression or boost which can lead to a more efficient engine.

I don't think my scanner can measure duty cycle, otherwise I would try different blends.

The long term fuel trim is at -4.7%

29 mpg highway and freeway and city
32 mpg 75 mi/hr freeway

When I measure mpg first I tell the attendant to fill the tank. Then I start my trip odometer. Then the next time I get the tank filled I divide miles by gallons.

I've also noticed that the vehicle is a lot harder to start even after a 50 degree night. It's not winter yet! I'm due to replace my battery so hopefully that makes it easy enough.

Ethanol just plain doesn't vaporize as easily so cold temps with a cold engine affect startability. Note that it can be bitterly cold, as in below 0F, and a warm engine will run perfectly on E85 even a non-FFV. For example if I'm doing a 300+ mile trip in bitter winter cold I can fill up early on in the trip with E85 and burn that down just fine, then I top off with regular so the next cold start is uneventful.

FYI: Your DX should have a 13.2 gallon tank.

The other main issue with this type of "conversion" is that it does not alter the injector dead time, starting and advance tables in the ECU. These will contribute to harder starting that gets worse at lower temperatures. I know of vehicles that run on E85 and methanol that start fine at very low temperatures, but they have had the ECU correctly tuned to achieve this.

Swapping injectors is at best, a crude hack that has the potential for lowered efficiency and engine damage.

Simon

What engine damage am I risking?

So far I don't think I'm getting lowered efficiency. The drop in fuel mileage is consistent with the change in stoich ratios.

I do have a megasquirt 3. I soldered it all together and made a harness. I did most of the sensor calibrations then I lost some data. It turned in to too much trouble. If you think what I'm doing now is hazardous I guess I'll have to get the MS going. I figured it would take so much work to get it running as good as stock.

The car has been starting right away after the second pass, ie, I crank the engine for about 3 sec, then let it rest, then it starts normally during the second round of cranking.

Running the motor lean and with incorrect (too low) advance risks significantly elevated exhaust temperatures that may burn exhaust valves. This is partly due to the slower burn rate of the alcohol. The lower advance will reduce power output and efficiency.

Have a look at pcmhacking.net - they have modded the Delco ECU to be real time programmable and there are lots of threads on using E85, albeit on Holden engines.

Simon

Don't wot or over 80% and it won't be hard at all.

Go wot into open loop on an aluminum engine and you can burn stuff

A snoot of either will make it start cold, also auto ether injection kits exist, I'm looking at one now for a cat.

In terms of increasing injector flow rates I would have gone very mild, maybe +10% since most Ecus have a very wide trim to begin with

Aluminium or cast iron will not make any difference unless your engine has exhaust valves made from unobtanium or the piston is cast iron!

Burning of the block or head is secondary to damage caused elsewhere, and is done by the burning gases "blow torching" the passage...

Ether makes my cat go to sleep, not wake up :D :rolleyes:

Simon

All the stuff you said is nearly impossible on a stock 1996+ with stock injectors.

You have to hold 15.5:1 Afr at wot for nearly a minute on aluminum motors.

Most cars are in limp mode with a cel which simply disallows your situation.

Myself and frank along with hundred of others on the e85 forums have a decade or more experience each burning it and the only cases I am aware of that holed a piston were custom motors.

Find someone who has burned their valves due to e85 and post it here, so we can dissect what he did wrong.

I will say that even though I lack instrumentation, when I get the CEL there are no symptoms, as in, CEL on and engine still runs perfectly, no stumbling, hesitation, or anything. So mixture must be good or at worst not that far off.

Different vehicles respond differently. Straight E85 in the Tempo will light the CEL 100% of the time until I blend in more regular. However, straight E85 in the F150 results in the CEL under some conditions and then it goes out. I figure pickups are allowed to go a bit richer than cars under some conditions because they are expected to work harder. Either way, the only operational issues I've seen with many years of E85 use are harder starting/stumbling when cold, all of which goes away once engine warms.

So you're saying that the fuel trims will cover me from over lean even in open loop, and that even if they didn't the limp mode would kick in? I guess I'm not really relying on fuel trims to protect from lean burn since the larger injectors that should be pushing all the maps high enough.

For some reason I thought that the timing advance was being automatically adjusted... but I don't have any evidence of that. It is worrisome about burning ports downstream of the valves since the fuel might still be burning.

I looked at the pcmhacking site. I can't find anything about compatibility with 7th gen hondas. I also searched for delco ecu's on amazon and the fitment calculator came up with nothing. I have the megasquirt if I needed to have a custom tune.

The way that it starts is strange, because it's just fine after the second round of cranking. I tried letting the fuel pump prime longer and that didn't help.

The issue I am having now is the decrease in vehicle range. Once I get my home fueling setup going that should be fine.

Thanks for the discussion, its been great!

Sameb, I mentioned that site as it has quite a lot of info on e85 conversions and what changes are required to get it running perfectly. Also, they have versions of the delco firmware that are customized and fully tuneable.

Simon

I hope you are running an E85 gas tank and fuel line compatible with high ethanol fuel, or you are a danger to everyone on the freeway, let alone yourself.

It's ALL been compatible for decades.

This is a very alarming statement. I wonder what you think about the claims here that corrosion is a non-issue for newer cars

https://www.change2e85.com/E85-Myths-FAQs


I would contact them, but I don't want to waste their time since I don't intend to buy their system.

well, I got in touch with the change2e85 people. they aren't too worried, and they sell a lot of injector only kits.

Well, you do you then. Personally I wouldn't risk blowing up a motor for the sake of running E85.

Oh please. I've yet to hear of that happening.

Right, because running E85 on a car that's obviously not set up for it is a good idea. Give me a ****ing break.

I'll just go run E85 in my insight now because you all think that's a good idea!

Then you are putting a band-aid on a bigger issue. I still wouldn't run straight E85 in a car that's not set up for it. You are asking for trouble. You are stressing the entire fuel system! It's like running boost and saying 'Yea, we don't need to add extra fuel, it's fine'.

The majority of engines that are certified to run at least e10 have fuel lines that are uprated to withstand almost any fuel in automotive use.

(Legislation has a minimum for the materials used in a vehicle)

But still wouldn't recommend that stuff in a car that isn't made for e85. It'll usually just become too lean, CEL goes on and the car adjusts for limp or uses a "safe" fuel map.

Nothing blowing up.

Go for it! :thumbup:

I've been running it for YEARS. And I don't own any FFVs.

And... I am giving you a break by not going all Frank Lee on ya! :eek:

P.S. Both tanks in my '94 F150 are full of E85 as we speak. No explosions or nuclear fallout to report... yet. :eek:

there gotta be a curve/fine line, of course. the ethanol has a high oxygen content, as it is hygroscopic.

I want to remind you that I am supplying extra fuel to the cylinders by putting in bigger injectors. Everything else is stock. It is putting more stress on the fuel pump, but it doesn't seem to be causing any problems.

I've seen folks using Brazilian-standard E96h hydrated ethanol without any problem in many non-FFVs that were also not dedicated-ethanol, including motorcycles. If it didn't harm them, E85 would fare even better.

I put E85 in my (stock) 1990 Legacy wagon, and it my wife's stock 92 corolla.. Corolla did NOT like it, ran ok but wouldn't idle right and would stall. Subaru I noticed no difference other than after a tank of E85 my wonky fuel gauge worked again. Both seemed to run better afterwards, the Corolla I had to run down to 1/2 a tank or so and fill with regular gas... But I did discover if I filled the tank 1/2 with E85 and the rest with unleaded, it ran like a top.

I feel like I can actually contribute to this thread in a meaningful manner, so I'll give it a shot.

There's a couple things to know about E85 as a fuel and as it relates to MPG:

Everyone already knows that increasing the thermal and flow efficiency of the engine will improve MPG; what most people don't realize is that Ethanol is a superior fuel for improving efficiency.

What I mean is this:
The two easiest ways to improve efficiency of a vehicle's engine is to improve airflow into and out of the cylinders; headwork, cams, larger intake and exhaust piping, etc. The other is to increase the compression ratio, leveraging more of the heat produced from burning the fuel into kinetic energy.

Ethanol has a much higher octane rating than pump gas, and will allow an engine to leverage a higher static and dynamic compression ratio, thus improving economy.

I'm currently in the process of rebuilding the engine in my car specifically to run on E85; this includes but isn't limited to cams, headwork and, of course, the highest compression ratio I can stuff in there via custom pistons and rods. With this engine, I expect to be able to easily exceed stated MPG of the stock car on full E85 fuel, while also making somewhere north of 400 horsepower to the wheels.

Questions? Comments? Let me know. I've done a TON of research on this as it pertains to direct injection and my specific car; might be helpful.


Side note:
Are you affiliated with SP63 or just using their site to pull the study from because it's convenient? Not slinging mud, just curious.

Also, keep in mind any "flex fuel" vehicle isn't optimized for either high blend ethanol fuels or straight pump gas, but are a compromise between the two.

As an example: on my almost entirely stock engine car (before I blew it up), I was getting better than stock MPG on a 50/50 mix of E85 and pump gas (about E45 or so), but that had everything to do with the tune and driving style. It was even better than most people were getting with non stock tunes/mods and straight pump gas, to the point that quite a few were astounded since they thought they got really good mileage themselves.

I ask because they are an engine builder for the platform my car is based on. Go figure.

I'd like to chip in to say I'm in the process of switching to full e85. Gradually adjusting by adding a higher proportion of ethanol each fillup. Currently on 66% ethanol and no difference in running or starting, but I'm sure the block heaters we use here help. Btw here it's Re85, made from recycled kitchen waste so quite eco-friendly.

With regard to the open loop cold-start/WOT accel. conditions, i believe that at least on my car the ecu uses closed loop fuel trim values to extrapolate the open loop fuelling. This should make it at least roughly correct. I suppose a cheap strap-on EGT sensor could be handy to check all is well. I haven't yet fitted a wideband lambda gauge, but that might also be a good idea.

Where I live, E85 actually means E90, and has for the past several years.

I rather see e100 hydrous, takes half the energy to produce