The quality of the gas makes a difference
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From: Mississippi
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From 2011 F-150 Owner Guide (3rd Printing), page 397:
Octane recommendations
3.7L V6/5.0L V8/6.2L V8 engines
Your vehicle will run normally on 87 octane regular fuel. Premium fuel
will provide improved performance.
3.5L V6 EcoBoost™ engine
Your vehicle is designed to run on regular fuel with an octane rating of
87 or higher. For best overall performance, premium fuel with an octane
rating of 91 or higher is recommended. The performance gained by using
premium fuel will be most noticeable in hot weather or in severe duty
applications such as towing a trailer.
3.7L V6/5.0L V8/6.2L V8 engines
Your vehicle will run normally on 87 octane regular fuel. Premium fuel
will provide improved performance.
3.5L V6 EcoBoost™ engine
Your vehicle is designed to run on regular fuel with an octane rating of
87 or higher. For best overall performance, premium fuel with an octane
rating of 91 or higher is recommended. The performance gained by using
premium fuel will be most noticeable in hot weather or in severe duty
applications such as towing a trailer.
Last edited by M-150; Oct 15, 2011 at 07:59 PM.
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From: Southern Indiana
I haul gas for a living. I haul for Marathon and Citgo out of the same terminal as Shell, Valaro, Conoco/Phillips and several other brands. The only difference in the additives and that are more tracers than anything. Their may have been some moisture in the gas but not much. To much and the ethanol will separate from the gas. (phase separation) Almost sounds like the bad gas was really 84 octane gas that didn't have the ethanol in it. Most terminals mix 90% 84 octane gas with the 10% ethanol to get 87 octane.
5 Year Member
Joined: Aug 2011
Posts: 2,297
Likes: 325
From: Mississippi
I haul gas for a living. I haul for Marathon and Citgo out of the same terminal as Shell, Valaro, Conoco/Phillips and several other brands. The only difference in the additives and that are more tracers than anything. Their may have been some moisture in the gas but not much. To much and the ethanol will separate from the gas. (phase separation) Almost sounds like the bad gas was really 84 octane gas that didn't have the ethanol in it. Most terminals mix 90% 84 octane gas with the 10% ethanol to get 87 octane.
Just another member
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From: MA
Originally Posted by rhodeisland
Did you notice at the pump if it was ethanol?
Ethanol absorbs moisture out of the air and also doesn't retain its octane over extended periods of time because here in R.I. boats are advised not to hold more than two weeks worth of gas because of the above reasons.
Ethanol absorbs moisture out of the air and also doesn't retain its octane over extended periods of time because here in R.I. boats are advised not to hold more than two weeks worth of gas because of the above reasons.
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From: Southern Indiana
Race Red '12 XLT SCrew EB
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From: MT
E-10 drops the mileage in my Ecoboost 1.5MPG. Normally I run Exxon 89octane without ethanol and do about 16.8 city, 19 hwy. Currently doing about 15.1city, 17.8 hwy with Cenex 89.5 octane E-10.
Thread Starter
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From: 5600’ in Arizona
Rabbit, I think you may have hit the nail on the head - octane rating too low. The minute that premium hit the injectors it was game on!!
It was opined on bobistheoilguy that switching gas brands occasionally was a good idea because of the different additives; one would clean up after the other etc.
Don't know if that is true, but I do use top tier gas exclusively.
In Roundel magazine some time ago, BMW went cross country taking gas samples and checking for ethanol concentrations. The pumps here in Texas say "may contain up to 10% ethanol" but BMW's findings were a little different. Nationwide they never found an ethanol enriched sample with 10% or less ; every sample was over 10% by varying degrees. BMW was having a lot of check engine lights on new cars that couldn't be traced to anything other than the fuel; their finds confirmed that gasoline in the US tends to be greater than 10% ethanol content. I'm sure BMW reflashed their way out of the problem, but now they (and other manufacturers) are fighting the want to go to 15% ethanol!
My 2002 330ci absolutely hates ethanol enriched gas, but he gets by; I get the random "oxygen sensor out of range" trouble code and it is because he was produced before the ethanol program got started. All of his PCM parameters are set up for 100% gas. Was kinda tough; replacing every vacuum related part trying to solve the out of range O2 sensors problem when it was the gas all along. Write it off as cost of doing business I suppose.....
It was opined on bobistheoilguy that switching gas brands occasionally was a good idea because of the different additives; one would clean up after the other etc.
Don't know if that is true, but I do use top tier gas exclusively.
In Roundel magazine some time ago, BMW went cross country taking gas samples and checking for ethanol concentrations. The pumps here in Texas say "may contain up to 10% ethanol" but BMW's findings were a little different. Nationwide they never found an ethanol enriched sample with 10% or less ; every sample was over 10% by varying degrees. BMW was having a lot of check engine lights on new cars that couldn't be traced to anything other than the fuel; their finds confirmed that gasoline in the US tends to be greater than 10% ethanol content. I'm sure BMW reflashed their way out of the problem, but now they (and other manufacturers) are fighting the want to go to 15% ethanol!
My 2002 330ci absolutely hates ethanol enriched gas, but he gets by; I get the random "oxygen sensor out of range" trouble code and it is because he was produced before the ethanol program got started. All of his PCM parameters are set up for 100% gas. Was kinda tough; replacing every vacuum related part trying to solve the out of range O2 sensors problem when it was the gas all along. Write it off as cost of doing business I suppose.....
Originally Posted by ggallant1
A lot of people don't realize the difference between different brands of gas. It is especially telling in winter when gas stations start getting winter mixes. I try to stick to shell and chevron. Quality gas will improve mpgs and keep your engine running cleaner.
http://www.toptiergas.com/retailers.html
http://www.toptiergas.com/retailers.html