Filled up my sisters E85 Yukon ...now runs like crap.

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bondservant2

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it s a non flex-fuel engine. When I put fuel in I’m certain I used the E85 pump. It was a blue handle pump. I have called the gas station TWICE to verify that it was E85. But now after about 30-miles, the truck runs terrible and is throwing codes. Dealer said up to $1200 to remove the tank and flush everything out. Any other solution....?
I guess no good deed goes unpunished.....

ETA: it had about 5-gallons in the tank and I added about 10-gallons and burned through about 3-gallons. Should I just go fill it up from another station and see if it rectifies.....?
 
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HiHoeSilver

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it s a non flex-fuel engine. When I put fuel in I’m certain I used the E85 pump. It was a blue handle pump. I have called the gas station TWICE to verify that it was E85. But now after about 30-miles, the truck runs terrible and is throwing codes. Dealer said up to $1200 to remove the tank and flush everything out. Any other solution....?
I guess no good deed goes unpunished.....

Let's start with basics.

What year is the truck?
Go look in the glove box at the sticker with the RPO codes and tell us the "L" code.

Do not run it in the meantime.
 

OR VietVet

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If you decide to do it, put more fuel in, make sure it is the correct fuel and fill it to help dilute what is in there and give it a chance to work out. I am not suggesting you do that but if you do, fill it. Maybe even premium. Were you filling the tank at the same station your sister does?

Plus, what are the codes? Maybe the running problem has nothing to do with the fuel.

If it only had 5 gallons in the tank and then you put in 10 gallons, that is a 2 to 1 mix and if the fuel is the culprit I would expect that the problem would show up quicker than 30 miles down the road.
 

gat0r

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curious, why put e85 in a nonFFV?

from what i have read & heard, you dont want it to sit in the tank & fuel system for more than a few days.
as o-rings & rubber lines could have issues.



as mentioned above... dilution may be a possible solution to taking it to dealer.
premium & maybe consider an octane booster too.

probably better to siphon out as much as you can & then add the premium to dilute the remainder.
 

OR VietVet

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Yea, you can get the cheap hand pump or electric siphon's with the long skinny hoses and get out as much as you can and then have a 5 gallon can of premium and then drive to known good fuel source and fill it up.
 

swathdiver

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it s a non flex-fuel engine. When I put fuel in I’m certain I used the E85 pump. It was a blue handle pump. I have called the gas station TWICE to verify that it was E85. But now after about 30-miles, the truck runs terrible and is throwing codes. Dealer said up to $1200 to remove the tank and flush everything out. Any other solution....?
I guess no good deed goes unpunished.....

ETA: it had about 5-gallons in the tank and I added about 10-gallons and burned through about 3-gallons. Should I just go fill it up from another station and see if it rectifies.....?

The industry standard is for FlexFuel to come from yellow pump handles and yellow lines. Shell of course, uses yellow handles on all of their pumps. Then of course, there is labeling to help avoid confusion.

It's been 3 hours since you posted, I reckon you've solved the problem in the meantime. If not, I would fill it up with 93 for this and the next couple of tanks.
 

Bob2C

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Yeah. E85 is yellow. E15 is blue. Hmmmm


Sent from my iPhone using Tapatalk
 

iamdub

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I'm confused. Title says it's an "E85 Yukon", first post says it's a non-FlexFuel engine and he put in fuel from the blue handle pump which, as has been stated, SHOULD be E15.

What are the codes?
 

HiHoeSilver

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I'm confused. Title says it's an "E85 Yukon", first post says it's a non-FlexFuel engine and he put in fuel from the blue handle pump which, as has been stated, SHOULD be E15.

What are the codes?

Hence me asking for the L code.
 

Fless

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Pump handle color standards are not always adhered to. We have a Murphys in my area that has E0 (pure midgrade gas) with blue pump handles. Some of the other stations have diesel with yellow pump handles, not your typical green handles. Gotta be careful these days.
 

thompsoj22

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WTF? So many different choices out there, Here in the "held hostage by democrats" state of CA they use a technique called "extortion". You know exactly what fuel you are putting in because you are taking food off the table with every gallon you pump. My last chevron fill up with premium at $4.78 per gallon was $126. You are extreemly focused everytime you pull into a gas station, you stare at the pump in disbelief, you are never relaxed enough to make an error by grabbing the wrong handle! LOL. I know I know no politics, but it is soooooo ugly out here! Welcome to CALI, you can take a dump on the sidewalk and stick a needle in your arm in public, But let the meter run out on your parking space and it is a $75 citation, fail to pay, $335 fail to appear warrant issued for your arrest. Now for the original post, find a way to siphon as much as possible out of the tank, my opinion is to than add just five gallons premium and drive it at freeway speed until low level fuel light comes on than drive it another 25 miles and fill it with premium.
 

gat0r

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always good to look at label & not the color of handle. (as well as know the vehicle you are in)

i was traveling last year & noticed a station had yellow handles for diesel.
where all other stations i have seen are green.

stopped some guy from filling up diesel in his hybrid car. lol
 
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bondservant2

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Thanks to those who posted. My wife and I were out on a date so couldn’t respond. I have to clarify that I have never OWNED an E85 capabale vehicle and have zero experience with them. My confusion is because I was told it’s E85 , it has the yellow filler cap stating E85 but no flex-fuel emblems on it. A quick internet search and a GM website came up stating E85 but not flex. Again I have no experience with flex-fuel vehicles.

So I learned that ALL E85 vehicles are flex-fuel (yes..?) and should run fine on even “regular” unleaded. So I have to guess more than likely bad fuel. Although I have to agree the problem should have surfaced before 30-miles of travel. So I’m still confused and still wondering if I should just add good gas and run it....

I’ll check the codes on it when I am able.....it’s not at my house.
 

HiHoeSilver

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Thanks to those who posted. My wife and I were out on a date so couldn’t respond. I have to clarify that I have never OWNED an E85 capabale vehicle and have zero experience with them. My confusion is because I was told it’s E85 , it has the yellow filler cap stating E85 but no flex-fuel emblems on it. A quick internet search and a GM website came up stating E85 but not flex. Again I have no experience with flex-fuel vehicles.

So I learned that ALL E85 vehicles are flex-fuel (yes..?) and should run fine on even “regular” unleaded. So I have to guess more than likely bad fuel. Although I have to agree the problem should have surfaced before 30-miles of travel. So I’m still confused and still wondering if I should just add good gas and run it....

I’ll check the codes on it when I am able.....it’s not at my house.

Yes. Flex fuel simply means that the vehicle is capable of running on fuels that contain up to 85% ethanol (E85). They will also run on E30, E15, and regular unleaded (<10% ethanol) of any octane rating.

The L code from the glove box will simply verify that the vehicle does, in fact, have a flex fuel engine. Given your yellow cap, we'll assume yes at this point. Good thing.

Different model years use different means of determining the alcohol % of the fuel. Some have an actual sensor, some use a virtual one based on other data. They can certainly fail or get confused. A scan tool can be used to reset it, but this should not be performed with ethanol in the tank.
 
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bondservant2

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Took it to the Dealership that is open on Sunday and the diagnosis :

RPO code L29. Fuel filler cap is yellow marked E85.

Fuel in the tank tests at 75% alcohol. So the blue handle pump is E85 at this station. Which I did verify twice. The Mechanic was able to run it on fuel independent from fuel in the tank and the problem continued, so that rules out bad fuel - or so it seems.

There is a misfire on the #6 cylinder with a history of misfire on #4. Spark plugs and wires check good on both.

So the good news is that I didn’t cause it. It was coincidental to me fueling it. Bad news is that it’s still happening and possible an internal engine problem . Maybe a stuck lifter or related to the fuel rail / injectors.

It just sucks that it happened while I was driving. I feel somehow responsible.
 

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