mel3535

Are there any mods that help with your MPG, just curious because my 04 coupe,a4, barely gets me 20mpg and that's with lot of freeway driving,.I have asked this question quite a few times on the forum since i bought my car about 7 months back but there seems to be nothing wrong with my 04 a4 with now almost 20k miles. Nothing has gone wrong with the car, the car is bone stock beside k&N filter and drivers perfectly fine.

Does everyone get this kind of gas mileage or am i the only one,on a full tank i usually get around 250 miles before low fuel comes up in DIC, is this normal?

20mpg is not bad at all and i did not buy a vette for good gas mileage but I hear people on here getting 30mpg and wonder why i do not.

So any mods that can help me improve mpg? and is my mpg normal or what?

0331MARINE

Something isnt right. My car is over 420rwhp with a big cam and my avg is over 20mpg. Might want to start checking some things. Plugs, wires, air filter, fuel filter and so on....

mel3535

i think you were the first to comment on my thread like 5 months back, and i did have it checked by two mechanics, nothing is wrong with the car, well over 4k miles since i bought it and is now almost at 20k, the car runs fine and is stock, i have done oil change and just basic maintenance and still the mpg is the same.

0331MARINE

Do you drive the crap out of it? I drive pretty hard and still get pretty good MPG for the power I have.

mel3535

i was for a while and its was mostly city driving, then it was around 15mpg i would fill the tank and in about 180 miles i would have low fuel sign on the DIC , now its like 70% on the freeway and i get about 20mpg

mel3535

not even 15mpg, its was 13.5

this was my thread a few months back

http://forums.corvetteforum.com/c5-g...prove-mpg.html

BigTattooMan

Just for kicks get on the freeway, set the cruise and set the DIC to instant MPG. I know it's super accurate but I'm curious how much influence your right foot is playing into this

mel3535

at 70 miles the dic says 26mpg.Believe me i drive this car like its a prius or something, i never get on it any more when i was i was geting 13.5 mpg

and beside i always use cruise control which is set at 70 most of the time

REDEVIL

I'm right there with you. Lately I've been driving 60-70% freeway in Southern California and I get about 18-20 mpg. I have Long Tube headers, cat back, vararam and dyno tune. Even on my trip to Vegas last month I only got 25 mpg. I don't see how people are always posting that they get 30+ mpg. Could it be the gas is different out here? When I lived in KS I would always put in 93 octane, but only 91 is available in Southern California.

0331MARINE

I'm only about an hour or so south of you..

Jet-Jock

26 at highway speeds is close, the window sticker says 19/28.

Have you reset the Average while on the highway and drive for a bit to let it re-establish average?

What type and size of tires (if different from stock)?

What type/octane fuel?

What mileage?

When was the last plug/wire replacement (mileage) if it has been done and if so what wires and plugs were installed?

When was the last time the air filter and PCV was changed?

mel3535

did the mpg change after the mods? i would think that with CAI and a tune you might be geting higher MPG

mel3535

i reset my avg in the DIC everytime i fuel up and reset my trip A so i know how many miles i get on a full tank,

tires are stock good year f1

fuel is 91

about to hit 20k miles and the car was 15854 when i got t

oil and filter along with air filter changed in the last 2k

if i start the car and look where the needle is on the gas gauge then turn it off and start again most of the time the needle goes donw a little or will if i do that 2 or 3 times, does that have something to do with spark plugs or anything like that, it seems to me that i burn a lot of fuel every time i start the car

REDEVIL

It's hard to say because when I got the headers and tune, I swapped the automatic for an M6, so I wouldn't be comparing apples to apples. I think my car gets OK mileage, but not the 30+ that some people claim here. I'm not too worried about it, but it makes me feel better when others are closer to the manufacturers claim of 28 mpg highway.

renegad44

I don't have many mods, except the few in my signature, and I have only managed, I recall 25.3MPG on a road trip, a/c on, to my daughter in Frisco Texas. Usually on those road trips, I don't play with it (WOT) because of the amount of added weight of a little luggage, and stuff I bring to my daughter, in other words, to me, too much weight to worry about WOT, and that's the best I do on open highways. No complaints though, I'm satisfied.

Jet-Jock

On the reset at fill the area I'm trying to avoid is any interim city driving being calculated. If you're seeing 26's on instant, I'd like to see it reset then, continue driving and see what the average is when you exit the interstate (highway).

This vehicle is still a baby practically.

Sounds like you have corrosion building up on the fuel sender contacts, typical problem as a result of the design. This is why you hear folks talk about adding Techron or using gas with Techron because it cleans the contacts and fixes the irregular fuel level readings. You can use exclusively Chevron or Texaco Supreme or buy a bottle of Techron at the parts store and add it according to the label instructions.

20K on maximum performance tires is about right, so not seeing the tread remaining you probably are getting close to new tires soon. Those OEM EMTs have a 300 wear rating. So you've gone through a good portion of the soft rubber, they are probably getting a little noisy now and perhaps a little more bump steer effect. A new tire especially some of the newer generation tires will give you a little improvement in that MPG say 1-2. But as that tire wears you'll be back to the 26 area. Depending on your type of driving and if you want to remain with run flats, Michelin Pilot Sport A/S ZPs or the Pilot Sport PS2 ZP will suit the vehicle. Going to a non run flat will further increase your gas mileage.

Jet-Jock

Different back pressure values will affect gas mileage but you also have a tune, that can be adjusted some. What tires are you running. MN6 will get better gas mileage then the A4s.

You really have to work at hitting those high numbers, finding the sweet spot at cruise over a period of time to get the highest value. But you should be in the range of the 26-28 range in normal type highway driving.

burbleflyer

The only way you'll really find out what, if anything is going on, is to find someone with a wideband sniffer and get a street tune.

Kale

I haven't found the DIC to be really accurate. You may just need to do the math.

Mine is usually 1-1.5 mpg off.

My wife's toyota, however, is always spot on. It's strange.

Vetteman Jack

Well, chances are you won't see 30 mpg out of an A4 - the six speed cars can get that due to the two overdrives in the tranny.

I usually get around 27 mpg from my A4 out on the highway, but when doing combined city/highway driving, it drops to 23-25 mpg.