Average mileage on a tank of gas

[Dangermouse]

Oh dear,

I start looking for gas stations at around 100 miles. Mine is all suburbs commuting and my GasBuddy app tells me I average about 13.5 mpg

[vwdmc16]

i always can get 280+ miles a tank gotten 310 once and that took 13gal to refill so it was really at the end and ive still never seen the warning lamp illuminate

[awildermode]

Oh dear,

I start looking for gas stations at around 100 miles. Mine is all suburbs commuting and my GasBuddy app tells me I average about 13.5 mpg

If it makes you feel better, I am getting about the same. 12-13 MPG

[Sidaries]

Usually my car has 23 mpg, but if everything goes well it has 30 mpg and on car shows 15 mpg.
The more I traveled with one tank of gas was around 300 miles, but I prefer to fill it after 200-230 miles latest.

[David T]

You should always be keeping track of the gas mileage. It should be over 20. If it is below that or it suddenly changes it is a good indicator that something is wrong. Very common for the Lambda system to be non-functioning and to compensate someone messes with the mixture screw and richens the mixture to make up for the lack of the additional fuel that would have been provided by the Lambda. That and a lot of vacuum leaks. I use the 12.5 gallon # . That still leaves a little more if you "overfill". What you are doing is filling the hoses leading into the tank, they can hold a lot of fuel but if you have ANY leaks you will know it! Turbos will use more fuel than normally aspirated cars but only if you use the turbos. If you stay off them the mileage will be equal to an original 5-speed. When planning a caravan you always have to plan conservatively just in case someone has really low MPG or doesn't fill up or has a luggage rack with a lot of stuff on it, etc. I once got 350 out of a tank but that was all highway driving and I had a small can of gas just in case. I knew the car was in good tune and running well.
David Teitelbaum
David Teitelbaum

[Bitsyncmaster]

Your city MPG is so dependent on how you drive and how long you idle. Stop signs, traffic lights, warming up engine for testing something all reduce your measured MPG.

Do you drive around town in fourth gear? You need to drive in the highest gear as soon as possible.

Do you floor it when you start moving?

I have about 50 miles on my car that has used a half tank right now. I'm testing my Idle ECU and that uses a lot of gas with zero miles clocked.

[stevedmc]

Guys, keep in mind that a demagnatized speedometer can cause you to think you are getting low mpg. I used to think I was getting between 20 - 25 mpg and as it turns out I was wrong. My speedometer is about 10 percent off and this was affecting my cauculations.

For me 96 miles on the odometer is actually 107 miles (verified by Google Maps). I got 27 mpg on my last fillup and this was driving at 70 mph. If I had slowed down it would have been even better.

Disclaimer: I've got a carb

[David T]

If you suspect your speedometer is not accurate you can always cross-check it with a GPS or the mile markers on the highway nad a stop watch. If the speedometer is not accurate it can be recalibrated. Speedometers can be off because of old lubrication, the spring loses some tension, the magnet loses some power, there is slippage in the cables (the dust cover is slipping). At 60 MPH the cable should be turning 1000 rpm's. That is where shops calibrate to and speedometers are most accurate. Makes the math easy.
If the odometer is off the speedometer will be off too.
David Teitelbaum

[dmc6960]

Guys, keep in mind that a demagnatized speedometer can cause you to think you are getting low mpg. I used to think I was getting between 20 - 25 mpg and as it turns out I was wrong. My speedometer is about 10 percent off and this was affecting my cauculations.

For me 96 miles on the odometer is actually 107 miles (verified by Google Maps). I got 27 mpg on my last fillup and this was driving at 70 mph. If I had slowed down it would have been even better.

FYI, you have another problem than just a demagnetized speedometer. The odometer is directly driven off of the cable input. The magnets only control where the needle points. If you odo is off, you may still have a speedometer problem, but you may also have an input problem as well. Could be dustcap, angle drive, lambda counter, or the cables.

[NVAPILOT]

I get about 20 miles for every 3.78 liters

Automatic trans