You and sleepwalker seem to be missing the dirty injector point. It doesn't matter what the ECU does. If the injectors are dirty, then fuel efficiency drops. Acetone will clean the dirty injectors and restore efficiency and as a result, mileage. You need clean injectors before the ECU can do its job.

 

Hi Lugnut.

Cleaning injectors would appear to be something which is much more popular in the USA than it is over here in the UK.

Certainly our fuel is likely to be different to that which you get, as of course are your ambient temperatures.
However I remain skeptical about the impact of "normally dirty" injectors on gas mileage. OK so there will be some gum deposits on the tip if the injector but how does this significantly influence gas mileage since the ECU will increase pulse timing / frequency if the ECU senses a weak mixture at the O2 sensors. (Anyway might not a weak mixture assist in better gas mileage?)

I would agree that if the injector was so fouled up that they can only dribble this might impact matters but such conditions do not occur in my judgement occur using commercially available fuel over lets say 100k miles.
Your position possibly links back to the issue of atomisation.

Unfortunately a "back to back" ON / OFF / ON / OFF test is not possible in this instance since you can't return your "Cleaned" injectors back to "Dirty".

I also observe the frequency that fuel line filters seem to be changed in the States.... Why is this so popular. It certainly isn't over here!

The capacity of the fuel filter on most vehicles is designed to permit considerably more flow than max. fuel demand. Even when partially clogged it should still be able to supply more than peak demand. There is of course a limit to everything but changing every 20k miles (my perception) seems to be totally unnecessary.

However, if you have a MIL / CEL light come on with a misfire code it may well be one of the first components you would visit.

Take cover.....I'm ready for the "FLACK" from across the pond!!!!

Stuart

 

yes i mean them as injector cleaners.


[/quote] it's true because bad spray pattern will leave more un-burned fuel.

 

Flack? You're stronger than that, aren't you?

That would increase gas usage and thereby reduce mileage, no?

I wasn't trying to validate a test method since I think this whole thing is just another bogus romp. I didn't want RockSolid to claim success when all he would really be doing is cleaning his injectors. We aren't pretending to be scientists here interested in doing testing that will withstand assaults by the global scientific community. Crimminy, we're talking about the effects of clean versus dirty fuel injectors in real life. It's a simple concept that sleepwalker has acknowledged.

You know, I've noticed you have a prejudice against everything American. It shows in most of your posts. Now, it's your superior gasoline. You've even managed to include that ambient air temps in America are detrimental. You're beginning to sound like a loon.

 

Hi Lugnut.
I expected a bit of "flack" but no need to go personal!
I like America and have many friends there.
I think you need to re-read my posts with a less jaundiced perpective.
Where do I suggest we Brits have superior fuel. YES we have different fuel.
Where do I suggest your climate is worse (detrimental) than ours . Its certainly different.
I only observe the differences in American behaviour but don't normally draw conclusions whether this is good or bad. You've added that bit.
It's a fact that you guys seem to have a passion for changing oil, checking track, changing filters, plugs and cleaning injectors etc. vs the status over here. Whether this is appropriate (good), or not, lies with the person taking the action. I personally think it is overkill on post 2000m/y vehicles.
New parts are unlikely to perform worse than worn ones but don't forget the old adage "Why fix it when it ain't broke" (Think this is a saying from your side of the water)
I guess a key driver in all of this is the affordability of the action. Cars (even European ones) and parts are much cheaper in the States, gas is cheaper, disposable incomes are greater etc. I certainly wouldn't mind having those American attributes.
Mind you I prefer our version of the language but I guess you wouldn't agree. (Oophs I guess I've done it again in your eyes)
If you guys are really interested in gas mileage I don't understand why you have such a passion for gas guzzling SUV's and large cube engines although at least some of them are / were made by the company I use to work for for 40 years. (Land Rover)

I reiterate my original asertion.

I will try the Acetone proposition on my w220 S class which is only used for motorway 75mph cruising journeys from the same point a to b = 200 miles each time it is used. This should reduce at least some of the variables. I wonder whether I will get a reversible improvement for whatever reason. Jury is out until I get some results.
PAX or should I ready myself for another attack?
Stuart

 

You implied that American gas clogs filters and British gas doesn't. That our ambient temps cause problems and British ambient temps don't. "Overkill" implies the negative. I'm not even going to read the rest of your post. You're off on some tangent. Have fun.

The "test" I mentioned was to test gas mileage with and without acetone added to the gas. I asked RockSolid to make sure his injectors were cleaned first, otherwise the test may be skewed because simply cleaning dirty injectors will improve mileage. That's what this thread is about. I have no idea where you're going with this and as I said, I'm not going to follow you. If you want to set up some sort of over-complicated test of dirty injectors versus clean injectors, go for it.

 

Good advice. I've since spoken about acetone and gas with a chemist friend of mine who works in the auto industry.
Like Lugnut, he feels the only impoved mpg comes from the cleaning of injectors.

IMO, snanceki makes good points regarding testing in an uncontroled test: considering all the variables he mentioned.

There is a countervailing position on the same web page. Makes more good points to refute the claims of acetone improving mpg.
read here.

 

It would be difficult to test for a 1% or 2%, even 10%, mileage improvement on the street. I think any sane person is going to balk at a claim of 30% improvement. So, leave the controlled testing to snanceki.

The link you just provided supports my contention that adding acetone to the gas may show better results on older carb'd engines, as I mentioned earlier. Modern pressurized and computer-controlled EFI systems just don't need any help spraying the gas into a mist that burns nearly completely. In addition, modern emission control systems "capture" unburnt fuel and reroute it back into the intake stream.

 

Really!

My understanding is that a percentage of exhaust gas is recycled (EGR) in order to impact combustion efficiency and in so doing lower peak combustion temperatures which in turn reduces NOx generation......NOT in order to burn any unburnt fuel in the recycled gas.

EGR does not run continuously and is used only under certain conditions in order to assist in acheiving legislative emmission requirements.

 

What are you trying to be, a pimple on my ****?

You're drawing the wrong picture in your mind. You're thinking in exaggerations. The EGR valve burns some unbernt gas and so does crankcase ventilation. Not by the gallons or liters, but it happens. Any that isn't "captured" thusly is supposed to be burned in the cats.

Why don't you try a "test." I understand you have an obsession for them. Put your mouth over your car's exhaust tip and have someone start the car. Breathe deeply for several minutes or until you fall to the ground, which ever comes first.