MPT (Miles Per Tank)

Can someone help me out with this conversion? Basically, I don't know how many gallons a full tank can hold. I live in Montreal, Canada. We use liters and km here. On a full tank, I'm only getting about 320 km before the gas light goes on. In summer, I remember hitting 460 km at most. Had everything checked/replaced. nothing (visibly) wrong with car. How bad is this and what does it translate in mpg? THANKS!
 
I get 270 in my '02 P5, but I drive it like it's stolen. I never shift under 4000 RPMs, and usually higher. In town, I cruise at 3500 so there is enough power to hop if I need to get in and out of tight traffic. I get the same on the highway as in town, driving about 65-70 MPH in 5th.
 
hah.. that gas mileage is s***... I get 450 - 500 km on a tank driving around town in a very mountains area.... highway anywheres from 450 - 650 kms...


Weborific said:
Can someone help me out with this conversion? Basically, I don't know how many gallons a full tank can hold. I live in Montreal, Canada. We use liters and km here. On a full tank, I'm only getting about 320 km before the gas light goes on. In summer, I remember hitting 460 km at most. Had everything checked/replaced. nothing (visibly) wrong with car. How bad is this and what does it translate in mpg? THANKS!
 
OK, so I worked-out my gas mileage from Canadian to US.
The most (summer): 460 Km on full tank (55 litres or 14.5 Gallons)
20 MPG

The worst (winter): 320 Km on full tank
14 MPG

Brand new summer (Toyo Proxes 4) tires and new winter (Blizzak Revo-1) tires. New spark plugs (NGK) and new wires (don't remember name, but not high-end). Everything checks-out according to my friend/mechanic. They can't find anything wrong with it. What can I do? It's driving me crazy! THANKS!
 
Let me add... car is AUTOMATIC, MPG is low even when it's only cool outside (no need to idle long to warm-up the car) and most driving is highway where I've even used my cruise control like crazy for a week but still only got 14 mpg...
 
Weborific said:
OK, so I worked-out my gas mileage from Canadian to US.
The most (summer): 460 Km on full tank (55 litres or 14.5 Gallons)
20 MPG

The worst (winter): 320 Km on full tank
14 MPG

Brand new summer (Toyo Proxes 4) tires and new winter (Blizzak Revo-1) tires. New spark plugs (NGK) and new wires (don't remember name, but not high-end). Everything checks-out according to my friend/mechanic. They can't find anything wrong with it. What can I do? It's driving me crazy! THANKS!

That is a bad way to calculate. 14.5 Gallons is the capacity, unless you are driving the car dry (which is a no-no), you can't use that as your basis. Most people claim the gas light comes on at 12 to 12.5 Gallons of fuel (2-2.5 remaining). I'd actually track it by hand. Fill your tank up all the way (don't top off). Drive it down, go to the same station/pump and fill it up again, don't top off. Figure the miles you traveled (this is what your trip is for!), and divide it by the amount of gas you just put in.

Adjusting your calculations above, you are probably getting closer to 23 and 16 respectively. I've seen as low as 23 in my automatic, but never have I really gone below 20. It averages 26 since I got the car.

Tire pressure, weather, and seasonal fuel mixes can play a huge part in your mileage. Not to mention driving habits and engine/drivetrain conditions.
 
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mogi said:
That is a bad way to calculate. 14.5 Gallons is the capacity, unless you are driving the car dry (which is a no-no), you can't use that as your basis. Most people claim the gas light comes on at 12 to 12.5 Gallons of fuel (2-2.5 remaining). I'd actually track it by hand. Fill your tank up all the way (don't top off). Drive it down, go to the same station/pump and fill it up again, don't top off. Figure the miles you traveled (this is what your trip is for!), and divide it by the amount of gas you just put in.

Adjusting your calculations above, you are probably getting closer to 23 and 16 respectively. I've seen as low as 23 in my automatic, but never have I really gone below 20. It averages 26 since I got the car.

Tire pressure, weather, and seasonal fuel mixes can play a huge part in your mileage. Not to mention driving habits and engine/drivetrain conditions.



Thanks for your reply! I noticed something funny tonight that I must share with all of you. my tires "felt" under-inflated recently so I drove to a gas station and went straight to the air hose. The air hose has a built-in pressure gauge that pops-up when you press it to your tire's valve as you all already know. The pressure on the gauge read 30 PSI. Just a tad low. I then pulled-out my Accurite digital pressure gauge and WOW...it read only 22.5 PSI. I wasn't sure which was correct, but I was banking on the accurite. I inflated my tires to 33PSI on the Accurite. The gauge on the air hose read over 40PSI. I don't know how that can be, but I checked it with a third (non-digital) pressure gauge that I own and it confirmed my Accurite's readings. Basically, it can very well be that people are inflating their tires using the hose's pressure gauge and are therefor under-inflating their tires which is contributing to poor gas mileage in the winter time. I realize that dividing by 14.5 gallons is incorrect (as you've pointed-out), but it won't increase my MPG by much. In any case, the tire pressure seems to be my main culprit and after filling-up tonight, I am anxious to see what my result will be. I always fill-up until the pump stops and then re-set my Trip counter. Then see how many km until my gas light goes on.... I'm sure there's something else wrong somewhere... Will re-setting my ECU actually do anything like some of you have posted? Thank you all. Go out and buy a digital pressure gauge...WORTH EVERY CENT!!
 
When I lived in SLC, Utah at 5500 feet and always driving on the highway, I would get 400-420 miles per tank (normally 12.5 gallons) consistently, so about 33 MPG is what I normally calculated. All I had done to the car was a K&N filter.
sometimes I would get 460 miles to the tank. The highest was a non-stop trip to Idaho, got 480 miles = 38.4 MPG.

Now I live back in Northern CA at 60 feet, and drive 60% city and 40% highway, get about 340-360 MPT, so about 28-29 MPG. I have a Simota CAI and short shifter now. Want header and full exhaust soon. Any idea what power gains those would give me? I would port and polish my intake too.

I read once, but what good is the VTCS removal ? Better mileage from less restricted airflow?
 
I average about 28mpg, with a mix of city/highway driving. That gets me about 280-330 miles per tank, depending on how long I wait to fill up. I currently have on winter tires (205/50/16), cold-air intake, VTCS deletion, and an axleback (which doesn't affect anything).

I didn't start calculating my gas mileage until a few months ago, but I'm pretty sure that it used to be a lot better when I first got the car. In the spring I'll be putting on new wheels and tires, new air filter, and getting a good alignment done. Hopefully that will help things out a bit.
 
Calculating it is easy. Fill, record mileage, divide by gallons/liters added...continue...I consistently get 240-260 miles per fillup, which is at 1/4 tank. I also consistenly am adding 12.0-12.4 gallons, and calculate from 22-24mpg...Nearly all driving in town and short 3-4 mile drives.
 
Lately I've been averaging 400 miles on 12 gallons. Mixed driving, mainly long country roads at 55 - 60 mph.
 
i get about 300 miles when the light comes on...i gas up at about 312 or so...roughly 26-27 mpgs.....turbo auto FTW!(cool)
 
The past few fill-ups I've had the best ever with my clutch slipping but still getting on it a little in second gear. Around 320 but I live 2 miles from work so it's all city driving.

I have been getting 150-200 out of about 12.5 gallons since I put my turbo in 4yrs ago. 12psi is still too much fun to not "Stomp" on it. Wondering what it will be like at around 18psi in a few months?
 
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