I normally fill up with 10% ethanol here in South Dakota. I know the recommended is 87 octane regular, but is 10% ethanol 89 octane going to hurt the 05's engine? I only ask because I know they say some cars shouldn't run ethanol.

 

NickS, I am not positive about what Ford says. I know from experience that Gasahol runs like crap in my 93 5.0.
Michael

 

Shouldn't you be drinking your ethanol rather than using it for fuel.

 

EtOH or Nos but NOT MeOH!

 

It won't hurt the enginge per say but the rubber and plastic parts need to meet ethanol standards check ford sight for details on ethanol use in vehicals They useally have a green leaf flame looking emblame on them
Did some checking seems that things have changed since I last read about ethanol almost all vehicles since 86 can run it fine but I would still check to make sure

 

I believe in Illinois, all gas is required to be 10% eth...

10% Eth shouldn't be a problem for the '05 Mustang, methinks

 

i believe all cars are designed to run on 10% ethanol/methanol (maximum) I doubt it is a problem, but check the owner's manual

 

There's a gas station here that sells 85% ethanol gas (if you can call it that)....I swear that popcorn should be coming outta the tailpipe!

Damian.

 

Should tell you in the owners manual available on this site.

 

From the Owners Manual, it says to use Regular unleaded fuel.

It also notes that Ford endorses " ..the use of reformulated "cleaner-burning" gasolines"

 

I wonder if they mean ethanol? :scratch:

 

Ethanol= EthylAlcohol 10% should be ok in all newer cars from Detroit but better check the owners manual first.