Your trims will compensate but a tune will help.

 

Well, if that fuel becomes the norm around here I will take it back to Don.

 

I dont know on the BMW tho. I do know that in the vette going from E10 to E15 will cause "positive" long term fuel trims (LTFT's, fuel being ADDED) which will result in that "pos" amount to be carried over to the PE table (power enrichment) causing a "rich" AFR during WOT, this is for safety during lean conditions, thats why a tune to get your LTFT's to "0" or a tad neg will help and give you a few HP up top, neg fuel trims always lock on "0" for fuel added to PE at WOT. , mine are currently at -5% down low, I am still tweaking the midrange.

 

been running e85 in my ss silverado for 3 years now (diffrent injectors and tune) stock pump and lines. no problem!

I converted my vette to e85 for street driving and flash the tune for e100 when i go racing. i have been doing this for three years now with no problems to any components. (aftermarket fuel system)

fuel consumption is up due to the fuel having extra oxygen in the molecule but it is a good trade for lower cost, power gains and you can buy it at the pump!

 

Correctly tuned/set up would one expect a power gain from the extra 5% ethanol?

 

I would say not from the extra 5% but a tune always helps any car, besides its always "up to 15%" so you still could have E10 or lower.

 

Hi There,
Watching the Charlotte 500 on & off. They said that nascar is going to be using the 15% foumla. J. Johnson just went from 37th to 1st
robsc501

 

If NASCAR does use a 15% ethanol blend it won't be with a pure gasoline tune. Also they will be making any mechanical mods to the fuel system to keep it from breaking down due to 15% alchohol addition.

 

Wow. I just heard this news from a fellow C5-er and I am beyound angry with our "Know-it-All" politicians... I am being sarcastic of course.

These yahoos know nothing technical. We all need to stand up to this BS.

Ethanol production requires tremendous amounts of water, corn and electricity to manufacture... We need to be able to drink our water and eat our corn! The reduction in fuel economy is significant too!!!

Chuck

 

So what's the Govt's plan when they force cars that call for a max of E10 to use E15 and car owners experience major problems and have to pay major cash to fix it? If they are really going to only require E15 for 2007+ model year cars (I'm assuming they are designed for E15+ ?), then how are they going to make both E10 and E15 available?

This looks like another messed up Gov't brainchild idea. If they want to sell more ethanol, then make E10 mandatory in all parts of the country. I don't think some of the rural areas have any ethanol in their gas ... it's usually only large city areas.

 

I do quite a bit of business travel, and have yet to find anything less than E-10. My understanding is this is a government mandate placed on all states, but if there are exceptions, I'd love to know where the good fuel can be purchased.

Even our friends in Canada pump E-10 garbage. Grrrrrr.

IF we MUST be forced to use this crap, why must WE buy an additive to make it less damaging to our vehicles? Shouldn't the additive be in the fuel when we pump it at a fuel station? Notice I said "fuel" and not "gas". We can't buy "gasoline" anymore .

Now I know how the guys who miss the leaded fuel from the pre-1980's feel, and it stinks. I was too young to drive or understand then.

 

Document ID# 2000881

Subject: Usage of E85 Fuels in GM Vehicles #05-06-04-035C - (07/30/2007)

Models: 1997-2008 GM Passenger Cars and Trucks (including Saturn)

Customer Interest in E85 Fuel
As the retail price of gasoline increases, some locations in the country are seeing price differentials between regular gasoline and E85 where E85 is selling for substantially less than regular grade gasoline. One result of this is that some customers have inquired if they are able to use E85 fuel in non-E85 compatible vehicles.

Important: Only vehicles designated for use with E85 should use E85 blended fuel.

E85 compatibility is designated for vehicles that are certified to run on up to 85% ethanol and 15% gasoline. All other gasoline engines are designed to run on fuel that contains no more than 10% ethanol.

Notice: Use of fuel containing greater than 10% ethanol in non-E85 designated vehicles can cause driveability issues, service engine soon indicators as well as increased fuel system corrosion.

Using E85 Fuels in Non-Compatible Vehicles
General Motors is aware of an increased number of cases where customers have fueled non-FlexFuel designated vehicles with E85. Fueling non-FlexFuel designated vehicles with E85, or with fuels where the concentration of ethanol exceeds the ASTM specification of 10%, will result in one or more of the following conditions:

• Lean Driveability concerns such as hesitations, sags and / or possible stalling.

• SES lights due to OBD codes.

• Fuel Trim codes P0171 and / or P0174.

• Misfire codes (P0300).

• Various O2 sensor codes.

• Disabled traction control or Stability System disabled messages.

• Harsh / Firm transmission shifts.

• Fuel system and / or engine mechanical component degradation.

Notice: Use of fuel containing greater than 10% ethanol in non-E85 designated vehicles can cause driveability issues, service engine soon indicators as well as increased fuel system corrosion.

If the dealer suspects that a non-FlexFuel designated vehicle brought in for service has been fueled with E85, the fuel in the vehicle's tank should be checked for alcohol content with tool J 44175. If the alcohol content exceeds 10% , the fuel should be drained and the vehicle refilled with gasoline - preferably one of the Top Tier brands.

Repairs to non-FlexFuel vehicles that have been fueled with E85 are not covered under the terms of the New Vehicle Warranty.

A complete list of GM’s FlexFuel vehicles can be found in this Service Bulletin, or at www.livegreengoyellow.com.

E85 Compatible Vehicles
The only E85 compatible vehicles produced by General Motors are:

• 2000-2002 S-Series pickups with 2.2L (VIN 5- RPO L43)

• 2002-2005 full-size pickups and utilities with 5.3L (VIN Z -- L59)

• 2006 Chevrolet Avalanche, Silverado, Suburban, Tahoe with 5.3L (VIN Z -- RPO L59)

• 2006-2007 Chevrolet Impala, Monte Carlo with 3.5L (VIN K -- RPO LZE)

• 2007 Chevrolet Avalanche, Suburban, Tahoe with 5.3L (VINs 0, 3 -- RPOs LMG, LC9)

• 2007 Chevrolet Express, GMC Savana with 5.3L (VIN Z-- RPO L59)

• 2008 Chevrolet Impala with 3.9L (VIN 3-- RPO LZG)

• 2006 GMC Sierra, Yukon, Yukon XL with 5.3L (VIN Z -- RPO L59)

• 2007 GMC Yukon, Yukon XL with 5.3L (VINs 0, 3 -- RPOs LMG, LC9)

• 2007 Saturn Relay, Buick Terraza, Chevrolet Uplander, Pontiac Montana SV6 (Canada Only) with 3.9L (VIN W -- RPO LGD)

Notice:

• Only vehicles that are listed in the E85 Compatible Vehicles section of this bulletin and/or www.livegreengoyellow.com are E85 compatible.

• All other gasoline and diesel engines are NOT E85 compatible.

• Use of fuel containing greater than 10% ethanol in non-E85 designated vehicles can cause driveability issues, service engine soon indicators as well as increased fuel system corrosion.

• Repairs to non-FlexFuel vehicles that have been fueled with E85 are not covered under the terms of the New Vehicle Warranty.

 

It doesn't surprise me that so many people are ignorant of ethanol, both it's uses and effects. What surprises me is how they refuse to become educated. I guess it's just a whole lot more fun to run around wringing your hands and blaming the government for another perceived injustice.

 

Sorry to jump back a bit, but this always confuses me and I keep hearing varying things about LTFT.

Wouldn't positive fuel "trim" mean that fuel is being trimmed? And that it is reduce the amount of fuel due to a rich condition?

To the opposite end, if my reading is -2 on the fuel trim it would indicate that it was adding fuel due to a lean condition.

So, if we use more ethanol, we should see the LTFT go further into the negative, right? example, -1 to -5

 

I still want to know what the Gov't expects us to do if they force us to use E15 (or even higher someday) in cars designed for a max of E10, and that causes issues with the fuel system, etc. Bunch of dumba$$es that don't care how much havoc they cause to the public IMO.

 

.) when you look at your ltft histograms positive numbers mean the pcm is adding fuel to make up for lean 02 readings - negative numbers the pcm is pulling (subtracting) fuel due to rich (typo removed lean) 02 readings

 

I don't have the do-hicky's to see all that, so I'll take your word for it. Certainly confusing though. I just assumed trimming fuel meant reducing.

 

Curious, aren't there guys on the forum that are running E85 with no problem? I know I've run E85 blended into my gas without noting any difference in drivability or damage. If going from E10 to E15 is such an issue, would going to E85 be even worse?

Really, I'm not being a smart @ss, I'm just not understanding what all the fuss is about. Also, I'm assuming that E10, E15, and E85 indicate the level of ethanol; 10%, 15%, and 85% respectively.

 

In the tuning world it's not spoken of as "trimming". It's called fuel trims.
Short Term Fuel Trims, Long Term Fuel Trims, Short Term Idle Trims and Long Term Idle Trims. They both add or subtract fuel depending what the averages are with the high and low range of your narrow band O2 sensors are reporting. (along with other calcs)

Adding alcohol richens the fuel mixture. Fuel trims will react to the new lower Stoch of the alcohol fuel sensed by the short term fuel trims and make corrections if necessary. Where the game changes is when you push the pedal down to a point where you enter Open Loop. Your O2's are no longer sampling fuel and making adjustments. You are now in a pre-set fueling mode called Power Enrichment (PE). No corrections are made for additional alcohol and you are running richer than when you were running straight gasoline.

Bottom line...you will get worse fuel mileage running alcohol...Period!
This is where the Fed. is screwing the public because they made these screwy deals with the Ethanol manufacturers. Not only are we paying for these new over priced Ethanol plants but the price of corn rises driving food costs up and we will be spending more for fuel because our fuel milage drops. We get to pay three times! But hey, it creates jobs so the politicians can get re-elected and think of more ways to **** our money away!

On the flip side if you tune right, add larger injectors you can make more power running 85% alcohol and you can really increase your timing table with not getting knock or spark retard! Just don't stray as far from the E-85 pump cause you will run out of fuel 33% faster!

 

Did you read Post #32 above?