MetroMPG.com mailbag: why don't you test acetone?

[MetroMPG]

MetroMPG.com visitors have sent me this question more than a few times.

The most recent:

Have you tried adding 2 or 3 ounces of acetone to 10 (US) gallons of fuel? I have read it increases mileage, but have never tried it.

The short answer is: no, I haven't tried it, and I don't have any plans to.

The long answer is:

• Testing fuel additives outside of a laboratory is extremely difficult to do, because of the lack of control over external variables that can affect the results.

• I will only attempt to test things that can be easily & quickly added/removed from the car so that data can be collected immediately before and after the change, under identical environmental conditions, in an A-B-A manner (and I should add: absent all other traffic, on cruise control, averaging bi-directional runs on a level, straight road). Fuel/oil additives obviously present a problem to that approach. And even this approach is far from the ideal.

• Some people have tried evaluating fuel additives (& other modifications) based on frequently repeated, identical trips in "normal" driving - e.g. their daily commute - despite varying weather & traffic conditions. I don't have a regular commute, so that's not an option for me.
  
  Besides, I'm personally not comfortable drawing conclusions from those conditions, because there's no control over changing weather & traffic variables, not to mention not being able to exclude the experimenter's own behaviour (driving) from the test.

Some people have persisted: Why don't I just try adding some and see if it makes a difference?

• Because not being able to do an A-B-A test under conditions that are as controlled as possible, I'd have little confidence that any difference I might see could be attributed to the acetone (or insert name of any other fuel/oil additive) vs. some other uncontrolled effect.

• On top of that, I haven't seen any sound scientific explanation for why acetone should work.

I tend to agree this skeptical view of acetone: http://www.fuelsaving.info/acetone.htm

It's worth a read if you haven't seen it already.

[Whoops]

FWIW: I don't have a scangauge. However I did try Acetone in ABA test. I didn't go any further because I ran the B level over 3-4 tanks of gas. I ran 3-4 tanks of gas, I didn't see any substantial improvement, to a level where it wasn't worth fiddling with, twice.

The way I look at it is maybe it works for some people. It didn't work for me, but if someone thinks it might, then they should give it a try, in their car. If it works for them, then I would say it seems to work for them and they should go ahead and use it, if they wish.

[MetroMPG]

One of the things I admire about the author of fuelsaving.info is that he sticks to his guns on the issue of valid empirical observations, even when it may weaken his own argument. He states up front that he hasn't tested acetone, and in the absense of any hard laboratory data either way, at the end he concedes:

"Admittedly, none of the above analysis proves that acetone doesn't help fuel economy."

(Though it's clear he's not actually giving any ground on his estimation of its worth.)

He also did allow that the addition of acetone may clean dirty fuel system components, so it may improve fuel economy simply by bringing things back into spec.

[kevlar]

Not to re-hash old threads, but I came across this one and thought I should throw in my 2 cents.

I started using acetone in my '96 regal 3.8 last summer and kept tight logs on it. It is a very shaky science as I watched it go from about 30mpg to about 33 mpg avg. I got lucky twice with the right gas, from the right station, with the right mix all in one happy tank . the two highest MPG's I was able to garner was one tank @ 35mpg, then once more a few tanks later @ 36mpg. Very hit or miss, and a fun experiment of which I have had no adverse affects. I have to say that there were almost NO improvements with winter gas (one to three mpg), which is another topic on it's own! How can you justify the ecological benefits of winter gas when you burn much more of it in the process?