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What is the purpose of the mileage left in tank readout if it is not accurate.
I fill my tank with 93 octane fuel and my computer says I'm getting 23 miles per gallon on a 120 mile roundtrip commute, averaging 70mph.
When I fill the gas tank my miles left in tank readout says 435 miles. When i'm done with a commute of 120 miles the readout drops way down to around 220 miles left in tank.
If i'm getting 23 miles to the gallon and i fill my tank to 14 gallons it equals 322 miles i should get. Why does the computer say i have 435?
I may be niave on this one and there's probably a good explanation for this, but would someone give me one anyway.
As always, thanks everyone
 

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I have an older version of the trip computer since mine is a 99. This is how mine works; The trip computer only calculates MPG when the car is in motion, therefore in stop and go traffic, your readings will be slightly off. Secondly you are using 6gals of fuel on your trip which is almost half of what your tank holds. The VW trip computer averages a lot and that is where the difference is. I did a 350 mile trip without any stops and found my trip computer to be off by 0.3%.
I dislike the VW trip computer because I have a BMW which has a trip computer also and it calculates MPG whether the car is moving or not and recalculates MPG left in tank accordingly.
 

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Trekie,

The computer does calculate AVG MPG when you are stopped. You will notice it most when you first fill up. Do this: the next time you fill up, set your computer to the avg mpg screen. Drive to your first traffic light, or just stop after a short distance and you'll see the avg mpg go down while stopped. Stopping will impacted avg mpg less and less the more you drive on the tank of gas and you will not see the drop on avg mpg.
 

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Re: Gas Mileage - Problem with computer readout, anyone else

VW2003 said:
What is the purpose of the mileage left in tank readout if it is not accurate.
Sure, it's accurate, it's just based on your recent average economy (not sure of the specific distance or time). For example, if you've got a 1.8T, you can floor it and keep the boost up, and note that your DTE will (after a very short time) start falling off. If you're coasting for a while, you'll notice your DTE will be very high to reflect that you haven't been using very much fuel recently.

In other words, it's more of, "If you continue using fuel at the rate you currently are, you will have this many miles left." (Also note that it doesn't take into account the reserve fuel of ~2gal in the calculations, just as the fuel gauge doesn't take it into account.)
 

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Sorry for the hijacking of this thread, but I've got a question that I can't find if it has been asked before. I also noticed from a picture on a different thread (turbo boost guage??) that the computer read out is similar to mine :crazy: .

Let me explain...

My MFC (= multi-function computer) shows my gas usage per miles in km, but it looks like it IS in mpg :???: . Avg. between 27-28 on the highway. Another case in point, temperature readout says 44 but the measurement indicator says C (celsius). Now if it was celsius it would be like driving around in a steam room :shock: . Am I reading this thing wrong :oops: ?

Any ideas....?

TIA
 

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Seriously :poke: ...

Someone must know what I'm talking about.

Next time you get in your car and flip to the temperature, does it give you the digits and a "C" in the upper left corner or SHOULD it be an "F" (for those of us living in the states)?
 

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RachaPassat said:
Seriously :poke: ...

Someone must know what I'm talking about.

Next time you get in your car and flip to the temperature, does it give you the digits and a "C" in the upper left corner or SHOULD it be an "F" (for those of us living in the states)?
If your car was sold in the states, it should use F for the temp and miles for the readout. If you bought the car used, then it's possible the prior owner switched to the metric system using a VAG-com tool. Is your speedometer calibrated in miles as the primary number? If not, maybe you have a Canadian car?
 

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You're right...it is from Canada. But I would think that the units would change from metric to imperial if the numbers are imperial (or appear to be that way).

It's hard to discribe, but just yesterday the temperature read 50, but the unit was "C". Could it be that changing of the units is a separate step from changing the numbers or am I stuck with having to pretend that it really is an "F" and not a "C".

Boy am I confused.... :lol:

Speedo is in miles as the primary indicator.
 

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RachaPassat said:
You're right...it is from Canada. But I would think that the units would change from metric to imperial if the numbers are imperial (or appear to be that way).

It's hard to discribe, but just yesterday the temperature read 50, but the unit was "C". Could it be that changing of the units is a separate step from changing the numbers or am I stuck with having to pretend that it really is an "F" and not a "C".

Boy am I confused.... :lol:

Speedo is in miles as the primary indicator.
Sounds like your cluster is going a little crazy... if it is registering 50 but displaying C instead of F, there is something wrong (unless it is about 120 degrees out :roll:)
 

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RachaPassat said:
You're right...it is from Canada. But I would think that the units would change from metric to imperial if the numbers are imperial (or appear to be that way).

It's hard to discribe, but just yesterday the temperature read 50, but the unit was "C". Could it be that changing of the units is a separate step from changing the numbers or am I stuck with having to pretend that it really is an "F" and not a "C".

Boy am I confused.... :lol:

Speedo is in miles as the primary indicator.
Okay, now I'm confused. Here's what I think you have going on, but I could be wrong (wife tells me that all the time):

If your speedometer has miles as the primary number, I'd guess this is a US market car. Next, I think the previous owner changed the MFA to read out metric. Third, I think the temperature sensor, which I think is behind the front bumper, is pranked and needs to be replaced.

I don't believe that the system is set up to change the units and then change the read out. But I guess the only way to make sure is to re-set the readout to US measurements....

Look on line for Stargazer's Passat page. In it, you'll find a list of the options for the MFA. Print that out. Next, find someone in your area with a VAG-com. Look on the Info Forum here at Clubb5. Buy a sixpack of beer and set up a meet with the VAG-com owner and have the MFA reset to US measurements. Leave sixpack as payment. :)

Then check and see if the readout is accurate. I doubt that the sensor will cost much to replace...good luck!

PS: How does the MFA show fuel consumption? MPG, Liters per 100 KM, or what? This might give a better clue as to what's happening.
 

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That's the funny thing. My mileage consumption shows on highway to be between 28-29/30. That to me appears to be MPG, yet the unit says X/100km. The distance readout says km, but the distance I travel is similar to the distance on my trip.

When I bought the car, Carfax stated it was from Toronto. Then it was moved to NY by the 2nd owner. I'm the third owner. When I test drove it I noticed that the unit for the temperature said "C". So I inquired about it's origin.

But when the temperature outside is freezing, it never reads 0 for celsius. It would show 32 degrees :suspicio: .

At least I now know I'm not crazy...
 
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