Fuel question (enlighten me)

[bssage]

The owners manual is pretty clear, No ethanol. I am curious why. I have some general knowledge about gasoline, octane ect... But in my neck of the woods I can buy 89 octane ethanol for the same price as the 87 unleaded. If my understanding of octane is correct. It refers to the point of combustion. And that higher octane not only burns hotter but more complete. And more complete = less residual gunk. I really am ignorant about the ethanol blends and how they effect the burn or combustion.

I dont have the book in front of me now. But I believe it also states that you can use between 87 and 91 octane. In this specific motor is there a benefit to using the higher octane ?

I am also wondering if there is a difference between the ethanol produced at the time of manufacturing and now. I know there have been changes and refinements in the last 12 years.

[tom4bren]

I can't enlighten you to the theoretical issues of ethanol but I can tell you that I've been running it in mine with no problems. I'm not even sure I can get ethanol free fuel in my area. I know that on my recent trip to TN, gas stations who sold ethanol free fuel made a point of advertising it & that doesn't seem to be the case here in VA.

[VX MileHigh]

From what I understand, the concern about using ethanol in any vehicle is that the ethanol can react with some of the gaskets and fuel lines in older vehicles. That said every time I am in Iowa I fill up a time or two with the 89 octane and don't have any problems.

[bssage]

After a little research I come away with a couple of things.

1. A lot of misinformation about fuel is out there.

2

One problem with ethanol is its high miscibility with water, which means that it cannot be efficiently shipped through modern pipelines, like liquid hydrocarbons, over long distances.[80] Mechanics also have seen increased cases of damage to small engines, in particular, the carburetor, attributable to the increased water retention by ethanol in fuel

WiKI

So the question becomes: Is the VX motor more sensitive to this water? It is the only thing that closely answers the question. And what is the definition of a small engine? A lawnmower: a Four cylinder: 6: ?

[89Vette]

It's not more susceptible to issues with water. VX MileHigh gave you the best clue. Ethanol can be hard on fuel system parts. Injectors in particular can be harmed -- if not rated for Ethanol. And, it's not necessarily something that can/will happen in a few days/weeks.

I'm not sure what year you're reading from in the manual, but this may not be true for all 3 years. At one point (in that 99-01 range), I'm thinking compatibility with ethanol fuels became required. And, it would depend on the factory's use of viviton vs. rubber seals + the type of injector. Maybe fuel filter and/or fuel pump too?

With a company/manufacturer selling a vehicle with 100k/10yr warranty, they would want to take every precaution against fuel issues. (IMO) It may be there's no issue. This would be a good question for Jerry Lemond.

[Scott Larson]

From the things I've heard and seen, ethanol can attack certain plastic and rubber parts used in the fuel system of older vehicles, degrading them to the point of failure and subsequent leaking or seizing as in fuel caps...The water retention issues really only have serious consequences with two-stroke engines causing them to run hot and seize. Let the debate begin!

[VX KAT]

From the things I've heard and seen, ethanol can attack certain plastic and rubber parts used in the fuel system of older vehicles, degrading them to the point of failure and subsequent leaking or seizing as in fuel caps...

Think methanol has anything to do with my fuel cap seizing up on my other truck???

Also, I'd switched over to regular 87 after I'd recently read I could use it instead of 91 or 92...so had been running 87 for a few weeks before it seized up.....

[Scott Larson]

Think methanol has anything to do with my fuel cap seizing up on my other truck???

Also, I'd switched over to regular 87 after I'd recently read I could use it instead of 91 or 92...so had been running 87 for a few weeks before it seized up.....

As I had stated in that other thread, yes I do... But then, it's just my two cents worth, which isn't much.

[bssage]

Its 2000. I will post other questions from the owners manual.

I have historically never been good at "doing what your told" without some reasoning behind it. Knowing why things are the way they are. Helps me evaluate new products and processes as they are made available. One of the reasons I ask is its safe to assume the process of producing blended fuels have changed in the last 12 yrs.

I dont see much on the part 2 of the question. Which is if the motor is designed to work with 87 to 91 oct. Is there any advantage to using the higher octane?

[SlowPro48]

Is there any advantage to using the higher octane?

Since the 6VE1 has knock sensors, 91 octane may yield slightly more power due to more timing advance in some circumstances.

I say may because the manual specifies 87 octane so who knows - that may be the basis for the mapped advance curve and the knock sensor circuit retards from that baseline - i.e., the upper bounds of ignition advance when the VX is running in open loop were tailored for 87 octane. Bottom line is if you're buying high octane, you're spending a lot more money for very little gain.

Anyway - please direct me to the source of this "No ethanol" info. It's not in the MY 2000 manual, which recommends that you use fuel with ethanol in it "to help clean the air". Are you maybe confusing ethanol with methanol?

And Larson it's lucky for you I don't have time to debate. You are WRONG, pooh-boy!!!! Oh BTW, you forgot this:

[bssage]

Well I got up went out and looked it up. Son of a gun. My first mistake in 2012. It reads "your vehicle was not designed for fuel that contains methanol." and says nothing about ethanol. And it little research is self explanatory. As it appears to be 114 octane.

So my bad I was one letter away from a real post.

[Scott Larson]

...And SloMo, it is lucky for you... cuz I am most def right, as indicated by the little fact that I did not forget this...
Ooops!

[SlowPro48]

Dammit I hate when that happens. Skimmed over them so fast I didn't see the argument bubble. I always screw up when I'm in a hurry. Guess that's why I gotta move in SloMo...

My apologies, Larson. Although you are still wrong about water only having serious consequences in two-strokes, (I can assure you, water in the fuel system will wreak serious havoc on a four stroke as well!) I was wrong about the emoticon and you are ri.. rig... righ.... righ.... Oh I can't even type it. Let me try another word.

You are correct, sir!


bssage, you are the Man! My first 2012 screwup was 234 days ago. And yes just one "C" can make a lot of difference!

[Scott Larson]

Ok, ok, ok, other then water possibly scoring fuel injectors in four-stroke applications, what are the serious consequences of water in the fuel for your average, everyday automobile engine, hmmmm? Pray do tell... (We're not talking 'bout frozen fuel lines, plugged filters, rough running, poor idle, etc., etc., etc.; what serious problems?) And we're also not talking about gallons of water in the fuel system and intake left to rust-up everything solid! We're talking about the amount of water that can be held in suspension by the ethanol blended fuel and ingested by the four-stroke engine in question. (Now remember, us old-timers can remember the day when high-performance aircraft engines ran water injection in the intake, so choose your words carefully.) GO!!