Poor Gas Mileage?

[niro884]

Im getting approx 186 miles to a tank in my car. I drive normally and don't push her very much. Is this about where it should be or is it poor? How do you calculate MPG?

Thanks!

[mbouse]

186 ÷ 11 = 17

miles driven divided by gallons consumed equals miles per gallon

seventeen is a very poor mpg for a Fiat Spider, of course, those results will vary depending on your driving habits...some restrictions apply, not legal in every state, void where prohibited

[kmead]

Are you sue you are really using up the whole tank? How many gallons are you putting in? The senders are not the most accurate after all.

[niro884]

Are you sue you are really using up the whole tank? How many gallons are you putting in? The senders are not the most accurate after all.

yes. using the whole tank. The sender is actually new. I cant figure it out. Car runs great. Too rich maybe? No carbon build up inside the muffler.

[narfire]

Hi there,went through this with mine. Bottom line is check the capacity of the tank I believe it's 43 liters. Being in Can., when you fill see how many liters you need to fill. If the light comes on at 300 kms and you put 34 L in then you have a bit more to go before it stops.(engine)
I found in my 80 I have a light at 310 kms but will go to 400 kms before fill,then 35-38L seems to fill the tank. 4.54 L/imp gal and 3.8/US gal. When I had a mpg gauge in the car, 220-250 miles was time to fill.

[joelbert2k]

I have a new sender in my 80 as well and the light comes on at around 185 miles. Last time I filled it when the light came on it only took 8.5 gallons which gave me about 22 mpg. I need to adjust the float, probably by bending the rod. I just don't feel like pulling it out.

Joel

[mdrburchette]

Is this a carbed or FI car? I fill my tank to the brim, drive it, then fill it back to the brim to calculate my mileage. Even my souped up Spider gets better than 17.

[RyanBorck]

This is the next thing I am going to have my mechanic look at.

When my gas gauge appears to be empty (has been running 5-10 miles with the light coming on), I fill it up but haven't been able to put more than 9 gallons in at a time (8.75 last fill up to be exact). I know I had the tank relined because it previously was rusted, etc. So I will assume the original capacity of 11 gallons has been reduced.

Either way, I only get 100-130 miles per fill up. I have estimated that my odometer is off by 3 miles for every 20 driven (i.e. I will travel 20 miles but it only shows I have driven 17). Even with that factored in, best I can calculate is I am getting a messily 14 MPG, tops!

So, I will let the mechanic have the car while I am out of town and have him figure it out. Once this thing is up and running with all systems in check, than I will learn how to start working on myself.

[mbouse]

easier than contacting your mechanic, put a 1 gallon can full of fuel in your back seat... drive like a bat outta hell until you literally fall to the roadside with zero gas. add the gallon and drive to the nearest fuel station and fill up. how much did you pump into the tank? easy-peasy simple study in fuel tank capacity, and you paid no one for a "correct" answer

fuel economy is no different in this car than any other. type of fuel purchased has little to do with fuel economy. especially when you consider that driving habit is the #1 variable, followed by engineering restraints.

i drive my spider like i stole it, every day, every trip. for speeds under 70 mph, i get a minimum of 25 mpg. when i have my throttle control along for the ride, at 50-60 mph average, i have seen as high as 31 mpg.

[Europa]

I fill it up but haven't been able to put more than 9 gallons in at a time (8.75 last fill up to be exact).

Ryan,

I filled up my Spider twice since I rebuilt the engine. I am getting approximately 27 mpg. Last fill up was 9.29 gallons and I ran 407 kilometers. That's about 253 miles and approximately 27 mpg.

[danaspider]

Having a history, when I was much younger, of running cars dry, I like the design of the light coming on with 2+gallons left. That way it is not a panic when it comes on. Just use it as a clue to be able to go faster due to reduced weight.


I agree with Mike on the milleage. My 79, never below 20, arounf 25 is good under normal drive, better on open road cruise.