Telcomans Fuel experiment (in progress...)

[pfarmer]

The whatever valve? you mean the shutter valve? take it from a tech, if its not acting up, dont get it fixed. The shutter valve gets replaced because oxidation causes it to stick and make the auto shut off at the pump turn off constantly when you press it down, making fill ups difficult. Ask steve, we hate doing those, as gasoline in your wounds and cuts is very painful, not to mention the process is not fun. anyway.....Perry, the car going into limp mode is because the ecm detects what is(or could be, if its just a faulty unit) a CATASTROPHIC failure, and goes into limp to protect the engine from being harmed by high revving or heavy load. Being low on gas won't cause the car to go into limp mode, since low fuel is just a variable resistance related signal, not an operational parameter reading that has direct correlation with preset and full-use statistical read-only phases for engine and drive management. There would need to be a confirmed dual trip detection logic fail or critical single trip malfuncion to cause limp mode behavior for driveline damage prevention.

I am speaking of picking up something in the tank like water, sugar or some other uglyness that then is fed to the engine.

Perry

[smockers83]

Yeah, that valve, haha. Couldn't think of the name off the top of my head. When I first got my G, the first couple of times I filled it up, I had the typical valve issue where it would prematurely stop (was the first reason I visited NICO). After a couple more times it seemed to not do it, but I also tried different nozzle positions. Now, it's starting to act up again, so yes, I may need to get it legitimately fixed. I'm not one to get something fixed if it doesn't need fixin'.

[Poyzinous]

water? sugar? you must live in a bad neighborhood if that stuffs happening. Sugar dissolves in liquid doesn't it? Anyway, water could be an issue, but I dont know how serious i'll take my fillups either way. Eric, show your tech some courtesy when you go get your new valve, make sure there is less than 1/4 left in the tank, to make the job easier on him and minimize fuel spilling into your interior and etc...

[bentrod]

For what it's worth - sugar is NOT soluble in gasoline. I faced this argument a 100 times in the claims business for those trying to get a new engine by saying theirs was vandalized with sugar. It's a chemically proven fact that no sugur will dissolve in gasoline. It may plug your filters, but that's about it!

[pfarmer]

For what it's worth - sugar is NOT soluble in gasoline. I faced this argument a 100 times in the claims business for those trying to get a new engine by saying theirs was vandalized with sugar. It's a chemically proven fact that no sugur will dissolve in gasoline. It may plug your filters, but that's about it!

Exactly!

Sugar will however get into more than just your filters depending on the vehicle. It will get into water separators if the vehicle has one, your fuel pump, fuel lines, and so on. The reason I brought up this up is that a low fuel level can allow contamination present in your fuel tank to cause problems.

You could easily see this on older cars where you had a glass bowl on your fuel pump. Water was easy to see, sometimes completely filling up the bowl. On carbureted cars, if you disassembled the carburetor you could sometimes find a bowl full of water as well. On many older cars your fuel sensor sat on top of the tank and was accessible from inside the trunk. Pull it out and you could look down into the tank and it was not all that unusual to find a certain amount of water. You could siphon this out and eliminate most of your issues. Want some real fun drop a small ball into the tank.

What many don't realize as well is that it is possible to have a biological growth in your tank as well. Any of these items can cause intermittent problems.

Perry

[bentrod]

LOL we must both be old if we remember glass bowls in the fuel lines...

[pfarmer]

LOL we must both be old if we remember glass bowls in the fuel lines...

I remember when Eisenhower was president, he died on my birthday.

I have owned about 30 cars, my first being a 53 Plymouth Cranbrook. It got almost exactly the same mpg as my 08 XS with 100 hp (maybe slightly more since it had a shaved head).

Perry

[BrandAidDesignG35]

If you had a contaminated gas tank, would there be any ways to treat or clean the tank, or can you just replace the fuel filter and hope for the best? I have heard sugar can ruin an engine... I'd rather not learn on my G.

[SVTCOBRA]

I dont know if gas station pumps employ filters, but i doubt they would let particulated fuel pump into customer's vehicles. what?

We have friends that own a fairly new BP station and they did say that they have the more advanced gas filters that not all stations have. Also, never fillup if you see a gas tanker dropping off fuel, it mixes up the junk in the tanks....

[pfarmer]

If you had a contaminated gas tank, would there be any ways to treat or clean the tank, or can you just replace the fuel filter and hope for the best? I have heard sugar can ruin an engine... I'd rather not learn on my G.

I doubt you will see sugar 'ruin' an engine, at least not directly. It could possibly by making it not run properly, but then that is usually a result of interuption of fuel flow to the engine. When I have seen this on the older cars, basically it would look like a syrup present in the fuel.

I think you are pointing to tossing some stuff in the tank to clean the contaminated tank. If you are getting particles I state you will not have much luck and you really want to directly clean the tank. If you want to dissolve a little bit of water, then your luck will vary. A lot of water, best just to bite the bullet in many cases pull the tank or access it in some way to draw the water out. A biological growth, well that can be interesting, you got to separate it from the sides of the tank and then remove it and in that case it sometimes comes off like it was some sort of tank lining, in other words comes off in sheets.

One of the nice things about the new cars is the trick with the small ball is much harder to pull off. I haven't seen that in probably 35 years.

Perry

[telcoman]

LOL we must both be old if we remember glass bowls in the fuel lines...

Well I'm not that old but I did have one on my 1940 Pontiac. I think my 53 Studebaker and 55 Chevy 6 cyl may have had them also?

[pfarmer]

Well I'm not that old but I did have one on my 1940 Pontiac. I think my 53 Studebaker and 55 Chevy 6 cyl may have had them also?

Probably on the Stude and the Cheby. I actually liked the concept, just loosen up the thumb screw, swing the retainer out of the way and dump it. If you saw something here that alarmed you, then the next step should be to look at the carb.

Perry

[telcoman]

So for all of you anxiously waiting for my MPG results on my first tankful of 93 Octane, I just filled up at 85581 miles.

I traveled 292 miles and it took 11.874 gallons to fill with a 24.59 MPG result at $1.97 a gallon. Regular 87 was $1,77 a gallon

My previous fillup on regular 87 Octane was 301 miles & it took 12.262 gallons for a MPG result of 24.55

So far I'm not impressed with spending the extra $.20 to $.30 a gallon but I will do a total of 4 tankfuls of 93 Octane and another 4 tankfuls of 91 octane and post my results.

Isn't there anyone else with an automatic or even another 6 speed willing to do this test and post results?

Telcoman

Here are the results of my second tankful of 93 Octane Premium

Filled up today at 85948 miles. Traveled 366 miles and it took 15.353 gallons for a 23.83 MPG result at $2.01 a gallon Sunoco.

Telcoman

[smockers83]

Hoping to start crunching numbers this weekend. The lady has to work this weekend and I need something to do. Last few weeks have been crazy. Got the G out a few weeks ago, went on a road trip for a bachelor party, and most recently, a wedding. Yes, wedding season has started.

[pfarmer]

Hoping to start crunching numbers this weekend. The lady has to work this weekend and I need something to do. Last few weeks have been crazy. Got the G out a few weeks ago, went on a road trip for a bachelor party, and most recently, a wedding. Yes, wedding season has started.

I wonder if we could not have another data point added into the mix in the future, that is the average mph as read from the car. This really will not make any difference in this survey but it does add a little bit for comparison purposes. For example right now I am getting about 21.8 at an average of 30.1 mph (using 91). Since all of this mileage is on 50 mph country roads and 30 mph city roads for this time period it is easy to see that most of it has been in town with a lot of stop and go. Anyway just an idea for those that wonder about the mix. In this particular case I believe most of his is highway.

Perry

[telcoman]

Hoping to start crunching numbers this weekend. The lady has to work this weekend and I need something to do. Last few weeks have been crazy. Got the G out a few weeks ago, went on a road trip for a bachelor party, and most recently, a wedding. Yes, wedding season has started.

Eric

Filled up today with the first tankful of 91 octane at 86608 miles @$2.00 per gallon, total $24.75 Sunoco

Here are the results of my fourth and final fillup of 93 Octane.

Miles traveled 319

Divided by 12.318 gallons to fill up = 25.90 MPG

Date Mileage Miles Gallons Pricel MPG Total Traveled Per Gallon Price to fillup



Telcoman

Modified by telcoman at 3:54 PM 4/29/2009

Modified by telcoman at 3:56 PM 4/29/2009

Modified by telcoman at 3:58 PM 4/29/2009

Modified by telcoman at 4:02 PM 4/29/2009

Modified by telcoman at 4:04 PM 4/29/2009

f*** it, I can't align the titles to the columns
Modified by telcoman at 4:07 PM 4/29/2009

[Joey666Crack]

Somewhat related, I talked to my dealer, and he said that he personally fills up with Mid Grade, and then every third fill, fils up with 93 to clean his injectors.

[telcoman]

Somewhat related, I talked to my dealer, and he said that he personally fills up with Mid Grade, and then every third fill, fils up with 93 to clean his injectors.

I really doubt if octane rating has anything to do with cleaning injectors?

http://www.usatoday.com/money/...lskip

The issue of which fuel grade and motor oil to use has a gazillion threads and opinions. I agreed to perform the octane test on my G to basically prove that a use of higher octane gasoline (Premium) has little or minimal effect on MPG.Temperature and humidity appear to have a greater effect on my gas mileage rather then the grade of gasoline.My mileage improves a few MPG with low humidity and temperatures in the 60 to 75 degrees F range regardless of the type of fuel grade used.My mileage is worse in winter particularly with temperatures below 20*F

Telcoman

[smockers83]

Crunching numbers today. Trying to relearn a statistical/data analysis program. Currently I'm importing data, which isn't hard, but I needed a break and figured I'd let you guys know the status of the project.Should be fun I'm probably over killing it (planning on regression analysis and other stats tests) but after I'm done, we'll know whether or not using premium is statistically significantly better in terms of MPG.Wish me luck.

Howie, got a question. The first 4 fillups are 93, now you're at 91. Elevation change, what's the reason? And are you completely done with premium now?
Modified by smockers83 at 12:12 PM 5/3/2009

[Poyzinous]

I really doubt if octane rating has anything to do with cleaning injectors?

I agreed to perform the octane test on my G to basically prove that a use of higher octane gasoline (Premium) has little or minimal effect on MPG.

Telcoman

That is correct. Octane doesn't do much as far as cleaning injectors. I've done these tests numerous times, to check that my own results were accurate. I found out some interesting things. Our sedans are programmed for 87 octane use. Using 91 or 93 will only help mileage by half a mpg. Not much to imply you're better off with it, but interestingly enough, on coupes requiring 91, the drop is more significant. Around .8 or .9 mpg when dropping to 87. The biggest thing octane rating does is directly affect power output. During testing, I found (through assistance of other people with the resources) that a car requiring 87 that runs 91 will produce a peak of 3% more horsepower, where as a car requiring 91 and using 87 will lose 5% horsepower. An FX35 is rated at 280hp. On premium. At the wheels, it produces about 225hp. Running regular 87 caused that number to drop to the low 210's. I got to see a 1/4 mile test with a 350z. .2 seconds faster with premium fuel. Many of you will also notice spark knock. My G can run regular, but I refuse to use it. I can tell when someone has 87 in their Infiniti because of the spark knock. By retarding the timing, the engine's combustion cycle is shortened, causing the loss of power. TELCOMAN, have you noticed better response between 2500 and 3500 rpm? You should. You will, gosh darned it. I did a test 2 years ago on my father's 2005 Pathfinder. 1 straight month on 87. It averaged 16mpg. On 93, 16.7 or so. But the biggest difference was the lack of spark knock on acceleration and the engine revved noticably better below 3000, as well as closer to redline. The conclusion I'm trying to give to you guys is that Upgrading from 87 to 93 has pros, but the pros dont outweigh the cons from downgrading from 93 to 87. Do you guys understand that? Heres a quick silly comparison. If you grow up drinking only bottled and filtered water, your body probably wont react well to drinking tap water. Contrairily (word?) if you grow up drinking tap water, and drink filtrered and bottled water, eh, not so bad.

[smockers83]

Prelim results are ready, which are probably the ones most of us will want.

I found that using the total miles traveled and total fuel used, using 87 rated fuel results in a MPG rating of 23.91. Using 93 rated fuel results (91 included as 93 assuming the rating compensated for elevation) in a MPG rating 24.57.

Octane - MPG87 - 23.9193 - 24.57

The total miles driven was 10951 and the total amount of fuel used was 456.268 gallons. The average price of all the fuel used was $2.72/gal. This will be our regular price for the cost analysis, which makes our premium price $2.92 using the general $0.10 increase between fuel grades.

Using 87 octane over 10951 miles would result in using approximately 458 gallons of fuel (found by using the overall MPG rating above). At $2.72/gal, this translates into $1245.76.

Using 93 octane over 10951 miles would result in using approximately 445.71 gallons of fuel (found by using the overall MPG rating above). At $2.92/gal, this translates into $1301.47.

The resulting difference is $55.71 dollars, it being cheaper to use 87 octane.

As gas gets cheaper, the difference becomes larger; the opposite is true as well. At current US averages ($2.07/gal for regular), the amount spent would be $948.06. Assuming the $0.10 difference, using premium would result in $1011.76 being spent for a difference of $63.70. If gas were $3.25 and $3.45, the difference would only be $49.20.

If we were to use these numbers to annualize the amount spent on fuel, we would see the resulting figures. Assuming the average miles driven per year is 12,000, using regular would result in using 501.88 gallons and using premium, 488.4 gallons. At today's US average prices, that would result in $1038.89 being spent annually using regular, $1108.67 using premium. The difference per year would be $69.78 more per year to use premium, but 16.48 gallons less in fuel used. This would also turn into one less trip to the gas station per year if you were to fill up at 15 gallons each time.

So, ultimately, it is cheaper to use regular, but at a cost. You get a worse MPG rating, which causes you to use more fuel. If you're looking to reduce your carbon footprint by using less fuel, thus oil, premium will be your choice of fuel. But if it's money you are looking to save, regular is your fuel of choice.

[pfarmer]

Prelim results are ready, which are probably the ones most of us will want.

I found that using the total miles traveled and total fuel used, using 87 rated fuel results in a MPG rating of 23.91. Using 93 rated fuel results (91 included as 93 assuming the rating compensated for elevation) in a MPG rating 24.57.

Octane - MPG87 - 23.9193 - 24.57

The total miles driven was 10951 and the total amount of fuel used was 456.268 gallons.

So, ultimately, it is cheaper to use regular, but at a cost. You get a worse MPG rating, which causes you to use more fuel. If you're looking to reduce your carbon footprint by using less fuel, thus oil, premium will be your choice of fuel. But if it's money you are looking to save, regular is your fuel of choice.

Where did you get the 10k miles? When I do the numbers I come up with:

91/93 octane 1618 miles / 65.863 gals

total cost - $123.058

mpg - 24.56

per mile 13.148

87 octane 1282 miles / 55.09 gals

total cost - $98.81

mpg - 23.27

per mile 12.974

91/93 octane 12000 miles x 13.148 = $1577.76

87 octane 12000 miles x 12.974 = $1556.88

A couple of other factors come into play however if you try to use a 12000 average for someone other than Telcoman. I brought up the average mph since if you are a high miler you most likely will be driving more highway miles, a low miler - more city miles. How does the average mph affect average mpg for the various fuels? I have a feeling that it is not simply linear

Second and I can only make an assumption here is that the higher octane run was made during slightly warmer temperatures. With my 'G' an increase in temperature helps my mileage although this may not be the case as it gets warmer still. However I do notice a difference between about 30-40 and 40-50. This may be skewed though by the average mph driven during these temps.

As far as the carbon footprint, that is a good point but you also need to consider a therm. For a worker how much longer do they have to work in a job with a higher carbon footprint? What is the carbon footprint of fuel production between the octanes, delivery, etc.?

Then of course maybe the factor of maintenance, does a lower octane few used by Telcoman cost more in maintenance (for Telcoman)?

Also for these figures don't we really need to consider the first load of 93 at the 87 average cost since that is what we are replacing in the tank? The same with 91 when going from 93? The same with total miles? You may have travel x number of miles when you filled up with 93, but those miles were done with 87 octane in the tank? Or did you do that, I'll have to run a second set to see if that was the case.

Perry

[telcoman]

Howie, got a question. The first 4 fillups are 93, now you're at 91. Elevation change, what's the reason? And are you completely done with premium now?

Modified by smockers83 at 12:12 PM 5/3/2009

I am done with 93. I will have the results of my first tankful of 91 octane tomorrow. I will fill up with three more tankfuls of 91 before I return to regular 87 octane.

I guess I'm not the only one that calculates MPG on each fillup?

http://www.nytimes.com/2009/05...1&hpw

SVT might like this one?

Telcoman

[pfarmer]

I am done with 93. I will have the results of my first tankful of 91 octane tomorrow. I will fill up with three more tankfuls of 91 before I return to regular 87 octane.

I guess I'm not the only one that calculates MPG on each fillup?

http://www.nytimes.com/2009/05...1&hpw

SVT might like this one?

Telcoman

I used to calculate on every fillup with a 63 VW. It had no gas gauge so it was usefull for figuring out your next stop.

Perry

[telcoman]

Eric

Check your email

I sent you additional documentation on my trips to Florida in May 07 and December 2008

The MPG clearly shows an increase in warm weather and a decrease in cold weather using regular 87 octane on long distance driving. My documentation clearly shows a sharp decrease in MPG when the wife used my G35 for short trips in Florida.

Telcoman

[Joey666Crack]

I really doubt if octane rating has anything to do with cleaning injectors?

http://www.usatoday.com/money/...lskip

The issue of which fuel grade and motor oil to use has a gazillion threads and opinions. I agreed to perform the octane test on my G to basically prove that a use of higher octane gasoline (Premium) has little or minimal effect on MPG.Temperature and humidity appear to have a greater effect on my gas mileage rather then the grade of gasoline.My mileage improves a few MPG with low humidity and temperatures in the 60 to 75 degrees F range regardless of the type of fuel grade used.My mileage is worse in winter particularly with temperatures below 20*F

Telcoman

I fully understand the basis of this test, and I appolgize for taking it a little off topic..

I also have a buddy with an Acura TL? RL? One of those, and supposedly, his Acura dealer told him that if he filled and ran low octane it would cost him something like 400 dollars for injector cleaning. Just throwing that out there, personally I have no experience with the subject, and I am in now way doubting your knowledge.

[pfarmer]

I fully understand the basis of this test, and I appolgize for taking it a little off topic..

I also have a buddy with an Acura TL? RL? One of those, and supposedly, his Acura dealer told him that if he filled and ran low octane it would cost him something like 400 dollars for injector cleaning. Just throwing that out there, personally I have no experience with the subject, and I am in now way doubting your knowledge.

This may be partly from the small billboard on top of the Shell pumps that make a big deal out of the high octane gas keeping your injectors clean.

Perry

[Poyzinous]

perry, carbon footprint is slightly affected as well. Since higher octane fuel is more refined and (usually) has more beneficial additives, it combusts cleaner, and from the tailpipe, a car running premium has slightly lower oxides of nitrogen, a little less carbon monoxide, and just a teeny bit less CO2. Ask an emission inspector(for non OBD2 cars that have to run off a dyno). An environmentalist would want to use premium in his car if he wants to do the absolute best when it comes to exhaust gases.

does anyone know the answer to this:If vegetarians eat veggies, what do humanitarians eat?

and joey, regular fuel wont hurt your injectors. I have never noticed someone needing injector replacement sooner than someone using better gas. IF it affects it, it may be by only a few thousand miles, since injectors (especially nissan injectors) can run for 200,000 miles or so.

[smockers83]

Where did you get the 10k miles?

I had lots more data from him to go off of, going back to 2006.

[Tampa G35 Sedan 6MT]

You guys are really doing great work and i can't wait to read more!

DJ