99 a4 coupe
mods
bassani rear xpipe
deleted cats
z06 mufflers
ziptie mod

i average generally 17mpg when i drive it rough.

ive noticed lately ive been getting 15 or less mpg.. I havnt been driving it much different than i normally do. same gas, mod's havnt changed.

any ideas guys?

 

Some states go to a 10% ethanol mix for the winter months. It will give you poorer MPG.

 

I am not sure, but I would guess that England Green living in Florida has someting to do with it

 

I have the same problem...I think it might be due to bad gas being sold during the winter months. Here is Oregon, the gas is bad period. Just bad. During the winter, it gets worse yet.

They add a higher percentage of ethanol during the winter months. But to be fair and factual, it is not the ethanol per se that causes the gas to be bad. It is the actual gas they add the ethanol to which is the problem.

Here's how they do it in Oregon: A high ethanol blend is created during the winter months. In order to save/make money, the ethanol is added to inferior gas. By adding the ethanol to the inferior gasoline, they get the octane rating up to spec. Rather than adding ethanol to saleable gas, it is added to unsalable gas and passed off as 87 and 92 octane.

It is a sham. There is a group here in Oregon that is trying to get legislation passed to stop this practice - sofar though, their efforts have been fruitless.

Undoubetedly, someone is going to respond to this post with ranting about ethanol having a lower BTU. Yes, I know that. However, this is not the gist of what I am saying. The gas itself is bad to begin with, and they use the ethanol to up the octane rating. The lower energy content of ethanol combined with the lower quality gasoline makes for a doubly bad gasoline that makes our cars run lousy.

 

I'd also check the various filters, tire pressure, and have the tune spot checked to verify your AFR is correct.

 

I agree it could be the winter gas blend. My gas mileage seems to go down a bit compared to summer driving.

 

Welcome to E-10 fuel. Debate the quality of the gas, but the consistent fact is, E-10 gas gets about 10% poorer mileage than normal gas.

And this is supposed to make us less reliant on imported oil.

Good news is, there's nothing wrong with your car.

Have a good one,
Mike

 

we dont use the blend in florida


.. possibly the car is running richer?

 

yeah i dont think florida uses any kinds of blends in the fuel... its possible that it could be running richer.. but why all of a sudden? never had the AFR checked to begin with.. or had it tuned.. the winter months doing damage to the car possibily because of the cooler air?

 

hah.. im sure EG does have something to do with it!

 

o2 sensors maybe

 

I thought all states were selling E10 now...

Cool, dry (denser) air will definitely do it.

 

Does this mean that E-85 will have 85% poorer mileage?