I think there may be a new additive in the fuel?

Hehe... the only thing I can think of:

Texas... is it cold out there right now? Could you be noticing the water vapor/steam from the exhaust more due to the cold temperature?

Probably not the case, but the only thing I can think of.

I've noticed that when using regular 87 octane in my truck, the engine seems to run more sluggish than normal but when I use 89 octane, it runs a lot better. I wonder if it's the oxygenated fuel in smoggy California during the winter time?

Probably some new "winter blend" for your state.

Kills me when I think of all the different formulations of fuel that have to be made to satisfy different state requirements for summer and winter. I'd have to look it up, but I think I heard there were something like 47 different state-mandated "blends".

Where I live right on the border between AZ and CA, it's anybody's guess which "blend" you're going to get at any given station on any given day.... Most of the time, we get the "Phoenix" blends; but when Phoenix drivers get "hungry", we're suddenly fueling with San Diego gas.... I have a habit of running my tank pretty low, then refilling. Usually takes a couple of stoplights for the '02 F150's EEC to figure out what's up when suddenly fed the California blends.

Maybe that's just because my truck is a "green" 4x4; Ford classified it with the "Low Emissions Vehicle" stickers on the windows. Probably has fuel tables that run tighter than a $2 watch..... I haven't yet noticed any big changes with a fresh tank of gas when I'm running the SCT generic "Tow Tune"; only when I set it back to the Factory Stock tune.

With all the additive blends, then toss in ethanol too. At the rack I load at in Shreveport, there's two blends at the moment-------Texas gas with a 7.8 RVP and Louisiana gas with a 9.0 RVP. (Vapor pressure ratings) The 7.8 is "Summer Gas" (although it's winter) The 9.0 is winter gas. They're adding another rack just for E85. Then you've got Diesel fuel. Two grades there too, three up north with ULSD, LSD & #1 fuel.

most gasoline now is actually E10 (contains up to 10% ethanol) not sure if thats enough to make a color change or not....personally I will be running E85(85% ethanol) in both the neon and the mustang(when the stang is finally moving again) because of the higher octane....that and the fact I like the idea that my gas is grown here in the USA, you lose 10-15% gas mileage, but since ethanol is cheaper than gas to begin with, it evens out

wicked93gs said:

most gasoline now is actually E10 (contains up to 10% ethanol) not sure if thats enough to make a color change or not....personally I will be running E85(85% ethanol) in both the neon and the mustang(when the stang is finally moving again) because of the higher octane....that and the fact I like the idea that my gas is grown here in the USA, you lose 10-15% gas mileage, but since ethanol is cheaper than gas to begin with, it evens out

Click to expand...

It's not really cheaper. Your tax dollars are subsidizing the ethanol production. And it's actually taking more energy to produce than gasoline. Not all gasoline is made from foreign oil either. Even when it is, you've got good old US labor processing the stuff. And all the support industries that go along with it.