robertbartsch

All our gas is now laced with alcohal by law. Apparently, this mandate was passed to keep the dumb corn farmers in Iowa rich.

Anyway, my cars hate this stuff. I've had two SES issues recently that were corn-gas related.

We don;t have any air pollution in NY becasue the wind blows out to the ocean.

I assume everyone else in America will soon have to deal with the same issues.

Are there any tuning tricks to help my cars digest the corn-gas?

horist

We've had up to 10% ethanol added to our gas here for as long as I can remember... never had a problem... you posted previously that you leaned the car out 12%... it's probably running too lean now

I'll try to find a stock 2000 bin from my car... you may be able to compare it to see if there are any changes made for cars sold in the midwest ... but I would set the car back to 14.7:1 for now... 12% lean and then you add gas w/more oxygen (ethanol contains more O2) ... that's leaning it even more and probably too much

also would help if you'd post up what the SES lights were

GuitsBoy

iTrader: (4)

Im also running the 10% ethanol on long island and Im not having an insurmountable issues with it. It should only make a 3% or 4% or so difference in your trims.

robertbartsch

OK I'll go back and check the codes. One was a PO300 multiple misfire I'm sure. Another was a cam sensor and crank sensor code.

I changed the plugs, wires, and both sensors. In addition, I ripped open the front cover and valve covers to check for cam walk and busted rockers, etc.

I returned to the stock tune and then removed some fuel and added some timing with Edit. The car runs good now, but I am convinced the SES issues were corn-gas
related.

My wife's car had SES issues too - that went away over time. We buy gas at different gas stations.

horist

have you done a CASE learn on this PCM yet?

git_sum

iTrader: (10)

Not to go off topic but corn is used to make moonshine, and personally if something like that is what they're using wouldn't it make the gas a higher octane and make it run better?

horist

Ethanol does raise octane, but w/10% max it doesn't make a huge difference...

Example: E85 is 85% ethanol and according to e85fuel.com it's 105 octane

However... Ethanol is more oxygenated than gasoline so it requires more to make the same power ... E85 is about 70-80% as efficient as regular gasoline.

So by adding ethanol to the gas, I believe it lets them use a lower grade of gas (lower octane) and then have the ethanol bring the octane rating up... it's still 93 octane since ethanol is used in a very small amount.

The problem is since the addition of ethanol to the fuel does create a different mixture than pure gasoline (I believe here in the midwest we even have special extra oxygenated fuel for the summer) it may take a little while for the fuel trims to adjust , during which time you'll be running too lean (though they should adjust pretty rapidly) Another issue I can see is if you're close to maxing your injectors out on 100% gasoline... the additional of 10% ethanol requires more fuel be sprayed intot he cylinders which could max the injectors (prolly mostly an issue w/99/00 26lb/hr injectors on bolt on cars)

P Mack

iTrader: (6)

So we wouldn't be shooting for 14.7:1 with E85?

edit: Nevermind, i saw the other thread in the racers lounge with 9.5:1.

horist

I'm not 100% sure if it's 9.5:1 but it's around there... also there was a post in here where someone brought up a good point... the O2 sensors detect stoich... they don't know exactly what stoich is they just no if you should be richer or leaner (which is why I think any pinging issues may just be the car having to learn the LTRIMs for the now more oxygenated fuel)

P Mack

iTrader: (6)

Yeah I was thinking the same thing about the o2's, they should still switch at stoich. Seems like you could solve all issues through the ifr table or the desired a/f ratio value. I'm assuming all the rubber seals in the fuel system can handle ethanol without breaking down.

horist

they can handle it but for how long (at least at 85% ethanol levels) who knows...

e85fuel.com has some really interesting info on it...

P Mack

iTrader: (6)

I guess you might need a new timing table with this fuel if it burns slower. Also I wonder how exhaust temps are affected.

On that website it seemed like most of the reasons not to convert a vehicle had to do with the pcm and emissions, and those wouldn't matter for most of the people reading this. I wonder if the guys at racetronix know if the fuel system would hold up to ethanol. I'd be willing to try it.

P Mack

iTrader: (6)

I think most people know this, but everclear is 95% ethanol. Maybe we should call regular gas 20 proof and e85 170 proof gasoline. j/k