Don't waste your money with Premium gas!

[SnitGTS]

So I've been looking up different things I can do to improve my fuel economy without going crazy, I figured since both Jus & Matt use Premium gas that it would be an easy way to get 5% better fuel economy.  Well, everything I'm reading is saying the opposite!  

 

It was amazing how they all disagreed with each other on things like windows down versus AC on, clean air filter, over-inflating tires, when to fill up, etc..., but they all agreed premium gas does not help!  So stop buying it!!!   :spend:

 

http://www.consumerreports.org/cro/magazine/2012/08/debunking-fuel-economy-myths/index.htm

 

http://www.csmonitor.com/Business/In-Gear/2012/0627/Myth-busters-Consumer-Reports-takes-on-alleged-gas-saving-tips

 

http://www.consumer.ftc.gov/articles/0098-saving-money-gas

 

http://www.cartalk.com/content/premium-vs-regular-0

 

http://www.forbes.com/2008/04/22/cars-mpg-gas-forbeslife-cx_jm_0422cars_slide_4.html

 

http://www.getrichslowly.org/blog/2007/05/30/how-to-improve-your-gas-mileage-23-top-tips-for-better-fuel-economy/

 

http://www.thedailygreen.com/living-green/blogs/cars-transportation/how-to-get-better-gas-mileage-broken-0519

 

Edit:  Just adding a few more websites.

 

http://auto.howstuffworks.com/fuel-efficiency/fuel-economy/how-to-get-better-fuel-economy1.htm

 

http://www.investopedia.com/financial-edge/0211/9-easy-ways-to-increase-your-gas-mileage.aspx

 

http://www.getrichslowly.org/blog/2007/05/30/how-to-improve-your-gas-mileage-23-top-tips-for-better-fuel-economy/

Edited June 23, 2013 by SnitGTS

[Jus-A-CMax]

Damn, how did I get a mention in this thread? Guilty of dumb wastage :spend: for using premium gas when OBVIOUSLY these reputable websites know far, far more than me, my car and driving. Yep, guilty as charged...I'll just go back to driving to my lil premium filling world and continue my route with 600+ miles tank, fill up on Premium, 600+ tank, fill up on Premium, 700+ tank, fill up on Premium, 800+ tank fill up on Premium....yeah, whadda I know... :redcard:

 

Jokes aside, I suggest all of you do you own testing and come to your own conclusion. I for one am not pushing anyone to use Premium - if you believe and feel its wasteful, go ahead and stop, or don't use it. Its a free country, as far as I know today.

Edited June 23, 2013 by Jus-A-CMax

[salsaguy]

i think it's not just premium gas but the brand as well. premium Arco crap gas is not the same as Premium Shell, Mobil, 76 or Chevron . there was an interesting article i read where it talks about how if you change brand each time you fill up you are creating a new gas blend so it's best to stick with one brand for at least 5000 miles then switch to a different to get the best life in your car and minimize deposits and crud in your tank.

 

what brand did you use snig?

see here:

http://www.toptiergas.com/retailers.html

Edited June 23, 2013 by salsaguy

[SnitGTS]

Damn, how did I get a mention in this thread? Guilty of dumb wastage :spend: for using premium gas when OBVIOUSLY these reputable websites know far, far more than me, my car and driving. Yep, guilty as charged...I'll just go back to driving to my lil premium filling world and continue my route with 600+ miles tank, fill up on Premium, 600+ tank, fill up on Premium, 700+ tank, fill up on Premium, 800+ tank fill up on Premium....yeah, whadda I know... :redcard:

 

Jokes aside, I suggest all of you do you own testing and come to your own conclusion. I for one am not pushing anyone to use Premium - if you believe and feel its wasteful, go ahead and stop, or don't use it. Its a free country, as far as I know today.

 

Jus, I didn't mean any disrespect, just you and Matt are getting the best mileage of anyone I know and you both use premium.  I do not trust any individual website or organization, everyone has their biases, but not one site I found was in favor of premium over regular for fuel economy.  By all means, if you want to keep using premium it is your decision what you put in your car.  I was convinced that premium would give me better mileage from reading different posts from different people in this forum, because of that I even posted that I thought using premium helped someone get better mileage.  I still may try it for a tank or two to see if it does anything for me, but it seems there is a consensus against it.  Even the ecomodder website does not mention premium in its 65+ ways to get better fuel economy.

 

http://ecomodder.com/forum/fuel-economy-mpg-modifications.php

 

 

i think it's not just premium gas but the brand as well. premium Arco crap gas is not the same as Premium Shell, Mobil, 76 or Chevron . there was an interesting article i read where it talks about how if you change brand each time you fill up you are creating a new gas blend so it's best to stick with one brand for at least 5000 miles then switch to a different to get the best life in your car and minimize deposits and crud in your tank.

 

what brand did you use snig?

see here:

http://www.toptiergas.com/retailers.html

 

I am not particular to a specific brand, I get gas at a couple different gas stations depending on where I am when I need gas.  My current tank that I'm getting 51.8 mpg with I used Exxon regular.  As I've only filled up once that's all my C-Max has seen, but I also fill up at a Shell and a Hess.  I've always calculated my mpg when I fill up and I've never noticed a major difference with any of my previous cars, it will be interesting to see what happens with different brands with the C-Max.

 

Edit:  I am always skeptical when organizations make claims about something being better than something else.  The best way to qualify their opinion, in my opinion, is to see who funded the study.  Amazing how people find results in favor of one thing or another if they are being paid by someone who has a horse in the race.  That's why when there was a consensus against premium giving you better fuel economy in these websites, I was surprised.  Big oil has a lot of money, you would think they would have funded a study or two to dirty the water on whether the more expensive gas is better for fuel economy.

 

Jus and Matt, can you try running regular gas for a tank and see what happens? (totally up to you of course)  If you guys see a drop in your mileage then I guess these websites could be wrong.

Edited June 23, 2013 by SnitGTS

[zhackwyatt]

Premium or not, I believe Top Tier Gas (http://www.toptiergas.com/) is important.

[SnitGTS]

Click on the "History of Top Tier" link to the right, you'll see that behind the top tier website is the gas company 76.  They are hawking how their gas has more additives that will remove those nasty deposits and will show you where to find a 76 station near you.  You can even watch a video and see what a supermodel thinks! (I'm not kidding!)

 

Just my personal opinion, I wouldn't trust anything she or they say.

Edited June 23, 2013 by SnitGTS

[zhackwyatt]

Click on the "History of Top Tier" link to the right, you'll see that behind the top tier website is the gas company 76.  They are hawking how their gas has more additives that will remove those nasty deposits and will show you where to find a 76 station near you.  You can even watch a video and see what a supermodel thinks! (I'm not kidding!)

 

Just my personal opinion, I wouldn't trust anything she or they say.

Top Tier was started by several automotive companies. http://en.wikipedia.org/wiki/Top_Tier_Detergent_Gasoline

 

I have no idea who runs that exact website, but it has the list.

 

Using cheap gasoline had put my life in danger with my Explorer.  I'll only buy Top Tier from now on.

[plus 3 golfer]

Premium or not, I believe Top Tier Gas (http://www.toptiergas.com/) is important.

Me too or those stations that state like Costco - 5X the EPA detergent additive package for both premium and regular.  

 

Here's the irony I see in using premium vs regular.  Premium gas can deliver better performance and FE for the times that the knock sensors indicate to the PCM to retard timing but most looking for increased FE are not driving for performance and thus the PCM would likely never need to retard timing.  

 

Engines are mapped for using a certain octane fuel. An engine mapped for using premium fuel can generally run regular (providing one does not drive as such to continually trigger the knock sensors.  I believe most cars will through a diagnostic code for excessive knocking. Engines mapped for regular fuel can run premium but generally any actual FE gain would be small. This is because the PCM will follow the base map in controlling timing as it has no way to know when one uses premium or regular fuel.

 

Of course the above assumes the specs of premium and regular are the same including heating value but for octane and the C-Max control algorithms for ICE emissions and performance are like other gas engines.   

 

I and others have found through testing of premium and regular fuel in our 1.8t and 2.6 liter B5 Passats (both require premium fuel), there was no conclusive evidence that premium delivered better FE than regular although IIRC my many tanks of premium averaged a few tenths of a gallon better than regular (like around 1% better).  Of course the C-Max may be different / noticeable as it gets 1.5+ times the FE of the B5s but I doubt any increase will pay for the additional cost "premium" of premium --- at Costco "premium" = $3.539 / $3.339 = 6%.  Like Jus says "Its a free country" do whatever one believes in.

 

Also, testing is extremely difficult to do as there are simply too many variables affecting FE and it would require many, many tanks of regular and premium to draw a conclusion.  It's also difficult not to bias the tests (since it's not a blind test) when one wants to "prove" a particular point. ;)   Thus, I will not be doing any tests on the C-Max (not even one tank as that proves virtually nothing).  I will simply rely on what I know about fuels, how engines operate, and the price spread between premium and regular fuel.

 

Here's a link to an article in Scientific American (how can this not be true). http://www.scientificamerican.com/article.cfm?id=fact-or-fiction-premium-g

"You rate the gasoline about how it knocks compared to this reference mixture," explains William Green, a chemist at the Massachusetts Institute of Technology. "One's that don't knock very much are the premium." ...[/size]But for standard cars on the road today, purchasing premium gasoline is simply paying a premium for a fuel that delivers no added benefits. "If you think you need it," Green says, "you're being very eccentric."[/size]

Edited June 23, 2013 by Plus 3 Golfer

[SnitGTS]

Top Tier was started by several automotive companies. http://en.wikipedia.org/wiki/Top_Tier_Detergent_Gasoline

 

I have no idea who runs that exact website, but it has the list.

 

Using cheap gasoline had put my life in danger with my Explorer.  I'll only buy Top Tier from now on.

 

First sentence under "Characteristics of Top Tier Gasoline" is:  "Gasoline marketers agree when they sign on to Top Tier that all grades of gasoline that they sell must meet the Top Tier standards: their regular grade gasoline must be at least as good as their premium gasoline in terms of its ability to attain agreed-upon standards for clean engines."  

 

I'm wondering if maybe you are reading Premium gas as from a specific brand or brands?  I'm talking about octane level, based upon my research yesterday you do not get better fuel economy with higher octane gas versus the regular 87 octane gas.

[SnitGTS]

Me too or those stations that state like Costco - 5X the EPA detergent additive package for both premium and regular.  

 

Here's the irony I see in using premium vs regular.  Premium gas can deliver better performance and FE for the times that the knock sensors indicate to the PCM to retard timing but most looking for increased FE are not driving for performance and thus the PCM would likely never need to retard timing.  

 

Engines are mapped for using a certain octane fuel. An engine mapped for using premium fuel can generally run regular (providing one does not drive as such to continually trigger the knock sensors.  I believe most cars will through a diagnostic code for excessive knocking. Engines mapped for regular fuel can run premium but generally any actual FE gain would be small. This is because the PCM will follow the base map in controlling timing as it has no way to know when one uses premium or regular fuel.

 

Of course the above assumes the specs of premium and regular are the same including heating value but for octane and the C-Max control algorithms for ICE emissions and performance are like other gas engines.   

 

I and others have found through testing of premium and regular fuel in our 1.8t and 2.6 liter B5 Passats (both require premium fuel), there was no conclusive evidence that premium delivered better FE than regular although IIRC my many tanks of premium averaged a few tenths of a gallon better than regular (like around 1% better).  Of course the C-Max may be different / noticeable as it gets 1.5+ times the FE of the B5s but I doubt any increase will pay for the additional cost "premium" of premium --- at Costco "premium" = $3.539 / $3.339 = 6%.  Like Jus says "Its a free country" do whatever one believes in.

 

Also, testing is extremely difficult to do as there are simply too many variables affecting FE and it would require many, many tanks of regular and premium to draw a conclusion.  It's also difficult not to bias the tests (since it's not a blind test) when one wants to "prove" a particular point. ;)   Thus, I will not be doing any tests on the C-Max (not even one tank as that proves virtually nothing).  I will simply rely on what I know about fuels, how engines operate, and the price spread between premium and regular fuel.

 

Here's a link to an article in Scientific American (how can this not be true). http://www.scientificamerican.com/article.cfm?id=fact-or-fiction-premium-g

 

+3, from what I was reading, the PCM will retard the timing (and thus creating worse performance) only if the car is rated for premium gas in the first place and you put in regular, do you agree?  

 

Our cars are rated for regular, so this should never happen with regular gas.

Edited June 23, 2013 by SnitGTS

[joe]

People using premium in a vehicle only requiring regular gas and getting better mileage may be affected by the unconscience effort to get better mileage - That is, they are trying even harder in their driving to attain better mileage.  This could also include people putting shutters on the front of the cars or little magnetic knobs on the roof to improve air flow, etc.  As we make modifications to our cars to improve FE, we might coast longer, pull back on the throttle sooner, accelerate a little slower, etc., because we're really trying hard to exploit our modifications for better FE.  To validate using premium, or adding devices for better FE, the vehicles must be tested in an environment that eliminates the human factor.

[KAL Cmax]

I run premium (93 octane) for the additives, not octane. Since it costs me an extra $5 a tank for premium, that's about $20 more a month on fuel. I also use synthetic oil since I am going 10k on an oil change.

 

I know it can be seen as a waste of money, but the extra cost of piece of mind is worth it. My fuel expense has dropped by over $350 a month since I switched to the C-Max. To me it is cheap insurance. I bought my C-Max a month ago today and now have 2,476 miles on it.

[zhackwyatt]

First sentence under "Characteristics of Top Tier Gasoline" is:  "Gasoline marketers agree when they sign on to Top Tier that all grades of gasoline that they sell must meet the Top Tier standards: their regular grade gasoline must be at least as good as their premium gasoline in terms of its ability to attain agreed-upon standards for clean engines."  

 

I'm wondering if maybe you are reading Premium gas as from a specific brand or brands?  I'm talking about octane level, based upon my research yesterday you do not get better fuel economy with higher octane gas versus the regular 87 octane gas.

I'm not arguing for using "Premium" gas (i.e. a higher octane). I'm saying to each their own, but I personally only use Top Tier Gas for the detergents.  I've said it before IMHO Premium (high octane) gas from a cheap brand is not as good as Regular (normal octane) from a Top Tier brand.

 

I run premium (93 octane) for the additives, not octane. Since it costs me an extra $5 a tank for premium, that's about $20 more a month on fuel. I also use synthetic oil since I am going 10k on an oil change.

 

I know it can be seen as a waste of money, but the extra cost of piece of mind is worth it. My fuel expense has dropped by over $350 a month since I switched to the C-Max. To me it is cheap insurance. I bought my C-Max a month ago today and now have 2,476 miles on it.

I think it depends on the gas.  As SnitGTS quoted, for Top Tier suppliers, Regular has to have at least the same as the Premium--already making the regular higher than EPA minimum standards.  Premium may or may not have more.  QT (http://www.quiktrip.com/Guaranteed-Gasoline) says they put the same amount of detergents in all grades of their gas as an example.

[plus 3 golfer]

+3, from what I was reading, the PCM will retard the timing (and thus creating worse performance) only if the car is rated for premium gas in the first place and you put in regular, do you agree?

 

Our cars are rated for regular, so this should never happen with regular gas.

The PCM does not know what fuel is in the car. It operates from a base timing map advancing and retarding timimg based on real time operating conditions. It will only retard timing more from the base map if the knock sensors detect detonation. Under normal driving most cars requiring premium can run on regular without detonation. Thus there would be no difference in performance. Under more spirted driving, regular fuel in cars requiring premium is more likely to detonate. The knock sensors detect this and the PCM retards timing, thus reducing performance.

 

Also, detonation can occur for a number of reasons like hot spots in the cylinder from deposits whether using premium or regular fuel. Again, it's not material to the PCM what fuel is in the car. What matters is if there is detonation detected by the knock sensors. It's just more unlikely to have detonation running a higher octane fuel than required by the car.

Edited June 23, 2013 by Plus 3 Golfer

[Adair]

I've never bought premium gas in my lifetime of cars...............until the last 2 tanks.

 

I buy from the Kroger station in my town, because I have *fuel points* from groceries bought there. That Kroger buys from Shell, I believe, because they share the points thing. 

 

All my 19 previous tanks with my C-MAX have been with regular gas. The tank before this one finished with 558 miles, 12.37 gallons of Premium used. The one before that finished with 503.9miles/11.38 gal of regular gas. 

 

The current tank is Premium. It remains to be seen how it finishes off. But this one will likely have some more highway miles than usual. Right now, though, my running average is 47.6, with about 250 miles on the tank, and 80 highway miles yesterday @ 69 mph on cruise.

[zhackwyatt]

I've never bought premium gas in my lifetime of cars...............until the last 2 tanks.

 

I buy from the Kroger station in my town, because I have *fuel points* from groceries bought there. That Kroger buys from Shell, I believe, because they share the points thing. 

 

All my 19 previous tanks with my C-MAX have been with regular gas. The tank before this one finished with 558 miles, 12.37 gallons of Premium used. The one before that finished with 503.9miles/11.38 gal of regular gas. 

 

The current tank is Premium. It remains to be seen how it finishes off. But this one will likely have some more highway miles than usual. Right now, though, my running average is 47.6, with about 250 miles on the tank, and 80 highway miles yesterday @ 69 mph on cruise.

I'm not convinced by that.  I started using Fry's (owned by Kroger) after having always used Chevron in the past.  After about a year I noticed a change in performance of my Explorer, including stalls and hesitations.  Bottle of Techron completely fixed the problem, and now I only  use Top Tier.  It is true that Shell and Kroger/Fry's share the  points, but I don't believe the gas is the same.

[JohnnOhio]

Using high octane gas does nothing for better mileage unless you have a high compression engine. It is added to retard the gas so that it doesn't ignite before the piston reaches the top of the stroke(knocking or engine won't stop ever with the key off). If the engine is doing this you need to run higher octane gas. Some people that need premium and don't use it are just destroying there engine. The low octane gas ignites while the piston is still moving up in the cylinder before the spark plug fires.

 

Just need to use the amount of octane the engine needs to operate properly. Anything extra is just a waiste of money.

[JAZ]

I know an argument from years ago was that premium gas was 'premium' because it contained additives to reduce knocking, but those additives did not contain the same energy potential as regular gasoline, so therefore a gallon of premium gasoline contained less energy than a gallon of regular, hence lower mpgs for a vehicle that could run on regular.

[plus 3 golfer]

 

Using high octane gas does nothing for better mileage unless you have a high compression engine. It is added to retard the gas so that it doesn't ignite before the piston reaches the top of the stroke(knocking or engine won't stop ever with the key off). If the engine is doing this you need to run higher octane gas. Some people that need premium and don't use it are just destroying there engine. The low octane gas ignites while the piston is still moving up in the cylinder beforethe spark plug fires.

Just need to use the amount of octane the engine needs to operate properly. Anything extra is just a waiste of money.

Many confuse preignition with detonation and talk about both as one but the two are quite different but they can be related. Higher octane reduces detonation not preignition.

 

Preignition is the igniting of fuel prior to the spark by an ignition source. Regular or premium fuel can ignite before the spark and is usually caused by a hot spot in the cylinder for example deposits. This does not necessarily cause detonation or knocking.

 

Detonation is the explosion of the last portion of fuel in the cylinder after spark or preignition instead of burning normally. Higher octane fuel reduces the liklihood of detonation because in essence the fuel flame spreads more slowly as it burns the fuel in the cylinder. If the fuel burns too fast based on when the fuel is ignited from the spark plug firing or preignition source, the last portion of the fuel can explode or detonate. This explosion is the knocking, pinging that one can sometimes hear.

 

Also, engine run on hasn't been an issue for quite a while as modern cars stop injecting fuel when the ignition is turned off.

[Sparky]

Using high octane gas does nothing for better mileage unless you have a high compression engine.

 

The C-Max has very high compression compared to similar cars.  The high CR allows more power and better economy if the ignition timing is optimal.

Since the timing is computer controlled, I think it would be.  The CR listed in the owners manual, page 345, is 12.3 to 1.

[obob]

I know an argument from years ago was that premium gas was 'premium' because it contained additives to reduce knocking, but those additives did not contain the same energy potential as regular gasoline, so therefore a gallon of premium gasoline contained less energy than a gallon of regular, hence lower mpgs for a vehicle that could run on regular.

"There is little difference in energy content of regular versus premium gasoline. They both contain about 111,400 British Thermal Units of energy per gallon"

 

from http://www.consumerenergycenter.org/transportation/consumer_tips/regular_vs_premium.html

[theblackcmax]

My father is friends with someone who owned a company who delivered gas to stations. And he said that some stations that are independently owned by certain people are a NO NO when it comes to premium gas. They will tell the drivers to dump regular gas into the premium storage tanks. He always said no and stopped delivering to them, but you don't know if everyone does that. Just be careful and try to go to stations which are corporate owned.

[fotomoto]

The C-Max has very high compression compared to similar cars.  The high CR allows more power and better economy if the ignition timing is optimal.

Since the timing is computer controlled, I think it would be.  The CR listed in the owners manual, page 345, is 12.3 to 1.

 

My former Volt required premium yet it only had a 10.5 CR much less than the CMax.  Numerous Volt owners including myself noted an instant decrease in mpg when using regular unleaded.  It was just habit for me to punch the unleaded button at the pump instead of premium.   GM has taking a beating in numerous reviews and forums about this requirement so (putting my conspiracy theory tin-hat on) I think maybe Ford decided not to specify or recommend premium fuel since a 12.3 CR should deem such.  

 

I scanned this thread quickly but I don't think I saw anyone say they tried premium in the CMax and not get better results.  

[SnowStorm]

The C-Max has very high compression compared to similar cars.  The high CR allows more power and better economy if the ignition timing is optimal.

Since the timing is computer controlled, I think it would be.  The CR listed in the owners manual, page 345, is 12.3 to 1.

The C-Max has an Atkinson cycle engine where, quoting Wikipedia, "The effective compression ratio is reduced".  The 12.3 value is most likely the expansion ratio (actual change in cylinder volume).  We can't compare the 12.3 ratio Atkinson cycle to the same ratio Otto cycle.

 

For me, I'm not convinced either way yet but am leaning toward the possibility that higher octane could give better mileage.  From a marketing standpoint Ford would hardly dare to specify premium even if it gave better mileage.  It just wouldn't fly in the hybrid buyer market.  I've used E0 87 so far and may try 93 at some point but it will be a difficult comparison to make - too many variables. 

[fotomoto]

The C-Max has an Atkinson cycle engine where, quoting Wikipedia, "The effective compression ratio is reduced".  The 12.3 value is most likely the expansion ratio (actual change in cylinder volume).  We can't compare the 12.3 ratio Atkinson cycle to the same ratio Otto cycle.

 

For me, I'm not convinced either way yet but am leaning toward the possibility that higher octane could give better mileage.  From a marketing standpoint Ford would hardly dare to specify premium even if it gave better mileage.  It just wouldn't fly in the hybrid buyer market.  I've used E0 87 so far and may try 93 at some point but it will be a difficult comparison to make - too many variables. 

 

Very good points snow.  I forgot the Volt ICE is otto cycle and enthusiasts are expecting an atkinson ICE in volt 2.0

 

This time of year is great for me to compare tank to tank as day to day temps can vary only a degree or two (hot is hot) but unfortunately with our kids out of school my driving routine is not.