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I just got off the phone with a rep from VWoA, I had send an email on regards to the poor gas mileage of my 1.8t (14mpg city), and that the dealer had checked it and said it was OK, but that is my wifes car, I would understand if I were driving the car, but I'm not. Anyways they call me and explain to me that they had called the mechanic that checked my car and again he said that everything was OK and that if I wanted to take it back, he would re-check it (I know that if I take it, he won't even look at the car and will say everything is OK).

She also starts telling me about driving habits and variations on the cars and that what is stated of gas mileage is not always true...blablabla, and then tells me to put in mid-grade fuel :weirdo: because the manual is wrong and a lot of dealers are recomending mid grade...


Is this right???? What should I do, I need your help....
 

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turbo = premium
try this first. it's not worth the dimes saved.
 

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VWoA is feeding you crap.
99blackmagic is right.
turbo=premium or more.
i know people running aggressive tunes and using highest pump octane
and supplementing with toluene. (equiv. of 97 octane or so)
without gory details, the higher octane should provide
better combustion at equivalent temps and thus a more
efficient burn.

what did the mechanic check that was "okay"?
 

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Discussion Starter #6
Gersting, the mechanic said that he checked with the computed and that everything read ok and nothing was malfunctioning

Rice Boy...does reseting the ECU help and if it does how do I reset it....
 

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car has an adaptive ECU that "learns" your driving style.
not sure how to reset on passat. on my t-bird you pull
fuse for ECU, try to start car (it will not, and it loses its
memory) replace fuse, start and relearn at idle for 5 min
and some driving

but there must be more wrong, but not throwing codes.
maybe a dirty/malfunctioning maf that has altered the
air/fuel ratio causing rich condition?
:???:
 

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A VW mechanic told me that they are telling people who drive their cars very easy to go down to midgrade gas. I have a vag-com and I tested my car on 90 octane to monitor when the ignition is pulled back to prevent detonation. In several 0-60 runs, the ignition wasn't retarded until 4800 rpm in second gear - that is about 8 seconds after I floored it.

I also know that the ignition can be pulled back quite quickly. This last summer in 90+ degree weather I had a 95 octane mix of 92 octane and 100 octane racing fuel. In those conditions, I would floor it from freeway speed and the ignition would be pulled back within 2 seconds.

My opinion is that for regular driving, mid grade is fine. In fact, if you are not pushing your car, premium may be too much. All winter I run midgrade because I don't have opportunities to push it and with the cooler air you get more power anyway. When its really hot, or when I know I will be horsing around, I run 92 octane. And all the time, I know my ignition will be pulling back if it needs to.

For this guys wife, I would go to midgrade.
 

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Dumb question: how are you calculating MPG? Fill the tank full, reset the trip meter. Drive the car through the tank of gas. Refill till full. Take the miles divided by the gallons.

I'm wondering if you're going by the computer readout MPG or maybe the gas guage is not quite right.
 

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AgVWB5 has a point. If I were to measure my MPG at 1/2 tank of gas, it
would be pretty bad...the guage runs light for the first half and then
slowly works through the 2nd half.

ganseg- it seems to me that there shouldn't be a case (with the exception
of financially) that premium could be too much. The original poster
is also from TX, which certainly doesn't have the winter-time
dense air charge that you must get up in MN...
to me the slight increase in cost for premium is worthwhile given
more efficient and lower combustion temps. I may also not
be ready for "regular driving"
gersting :p
 

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Man.. Even if I drove my car the hardest possible, I wouldn't be able to manage an average MPG of 14. Well, when bedding my brakes, I was around 10mpg, but that's accelerating as fast as possible to 60mph, hitting the brakes hard to 10mph, and repeating 8-10 times. I doubt your wife drives that way.

Chipped, and driving aggressively, I get between 18-20.

Find someone with a Vag-Com, reset the ECU, realign the throttle body, etc. This is stuff I've heard works for various problems but never have done myself.

-Craig
 

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outrun said:
Man.. Even if I drove my car the hardest possible, I wouldn't be able to manage an average MPG of 14. Well, when bedding my brakes, I was around 10mpg, but that's accelerating as fast as possible to 60mph, hitting the brakes hard to 10mph, and repeating 8-10 times. I doubt your wife drives that way.

Chipped, and driving aggressively, I get between 18-20.

Find someone with a Vag-Com, reset the ECU, realign the throttle body, etc. This is stuff I've heard works for various problems but never have done myself.

-Craig
Something is quite wrong... With 2 more liters and 4 more cylinders, I have to drive my W8 like a maniac to have my mileage drop that...... Never mind. Carry on.... :D
 

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Discussion Starter #14
Ag, I am calculating the mpg filling up the tank, driving the full tank and refilling and dividing, I know how to calculate the mpg. but its not giving me a decent mpg. My wife does not ram the accelarator she drives very conservative, in her old altima she used to get about 24mpg

If the ECU "learns" driving habits, do I need to reset the ECU for the car to learn my wifes driving habits or after time it will adjust???
 

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almtzc said:
I just got off the phone with a rep from VWoA, I had send an email on regards to the poor gas mileage of my 1.8t (14mpg city), and that the dealer had checked it and said it was OK, but that is my wifes car, I would understand if I were driving the car, but I'm not. Anyways they call me and explain to me that they had called the mechanic that checked my car and again he said that everything was OK and that if I wanted to take it back, he would re-check it (I know that if I take it, he won't even look at the car and will say everything is OK).

She also starts telling me about driving habits and variations on the cars and that what is stated of gas mileage is not always true...blablabla, and then tells me to put in mid-grade fuel :weirdo: because the manual is wrong and a lot of dealers are recomending mid grade...


Is this right???? What should I do, I need your help....
TIP transmission with A/C on and lots of lead-foot stop and go will do this, also too much idling in the AM to warm up on a cold day (or to keep the car cool on a hot day)

reset the "1" trip computer, go fo a highway cruise at 60 mph with cruise on (no stopping or accelerating) and flat ground and see what your numbers look like.

vagcom to look for excessive knock would also be good...if you get knock you get big-time timing retard = poor mpg.
 

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Is this strictly city driving you're talking about? If it's a lot of stop and go and only driving in the city, I usually get 14-18 MPG. The MPG will go up as your engine breaks in. My 2003 didn't start breaking in until after 5000 miles.

On the freeway at 70-75 mph cruise, I get ~34 MPG. Try driving on the freeway as scotty_passat suggested and see what your numbers are.
 

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i agree take it out on the highway and benchmark it


i was getting kinda of crappy gass millage on my v6 till i changed my habits

now i get about 27mpg average
 
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