Gas mileage.

[Longinotti78]

I just picked up a 78 spider. My first one was 25 years ago my second about 20 years ago. It seems to be getting terrible gas mileage or the fuel gauge is not working properly. What is the average km you can drive before the red light turns on. How many litres of gas does it take to fill the tank. I am currently driving 200 when the low gas light comes on. Please advise.

[PhillySpider]

I just picked up a 78 spider. My first one was 25 years ago my second about 20 years ago. It seems to be getting terrible gas mileage or the fuel gauge is not working properly. What is the average km you can drive before the red light turns on. How many litres of gas does it take to fill the tank. I am currently driving 200 when the low gas light comes on. Please advise.

I'm betting the float on your fuel sending unit is saturated which will cause it to sink below the actual surface level of the fuel in the tank. This will result in your light coming on prematurely as it's essentially like the mechanical switch in your toilet. I've been thinking to replace mine for the same reason. When mine hits 1/2 a tank the light will start to flicker and needle drops up and down hills and over bumps. I think it's just heavy and bobbing at this time, causing false reads. Unless it starts acting up above 1/2 a tank I'll likely leave it alone and consider it part of Bella's personality .

[RRoller123]

With a new float, I get the gas warning light very consistently after 8 gallons used, 200 miles, out of about 11-1/2 gallons total. 24MPG overall. '80 2L FI.

[klweimer]

200 miles per tank sounds about right. I have an 82 FI and figure about 20-24 MPG. When I'm driving the spider, MPG is not my first priority.

[DieselSpider]

if you are only going 200 KM/124 M on 8 gallons/30 Liters then you are doing quite badly.

The Spider should get between 20 to 28 mpg depending on how its driven while your getting around 15.5 mpg/6.6 kpl when you should be getting closer to 323 kilometers and 11 kpl.

I loose track as with the Diesel mine gets between 36 mpg and 52 mpg depending on how its driven. I have gone as far as 523 miles on a tank when driving conservatively using 10 gallons of Diesel getting about 52 mpg.

[spidernut]

According to the 1978 United State EPA estimates, the Fiat 124 Sport Spider should get 20 mpg city, 28 mpg highway. Therefore, you should be getting about 45 kpg if the car is stock.

[MrBlimp]

I am reading into this thread what may also be the cause/solution to my gas gauge issue. It seemed at first to be working. Then it seemed like it wasn't then it seemed like it was working like a tachometer instead of a gas gauge (fluxuating while driving). Then it seemed like it has stopped working all together.

The other day I was thinking that maybe I should gas up since I drove it about 60 miles or so since the last time I put any gas in the tank.

This time I filled it until the gas was just entering the fill tube. When I got back in the car the gauge read full.

I drove it 3 times since, approximately 60+ miles total, and the gauge started the fluxuation again.

[phaetn]

I just picked up a 78 spider. My first one was 25 years ago my second about 20 years ago. It seems to be getting terrible gas mileage or the fuel gauge is not working properly. What is the average km you can drive before the red light turns on. How many litres of gas does it take to fill the tank. I am currently driving 200 when the low gas light comes on. Please advise.

Is 200 km or miles? Is your speedo metric or imperial?

42 litres to fill the tank, according to the manual for my '74. I've put 40L into only once, most times less, and that was going from nearly dead empty to having gas up to the top of the fill tube.

Not sure if my mileage is good or not, but I've got a big carb and I suspect somewhat rich. I usually fill up after about 120-140 miles (192-224 km) of city driving and then it's somewhere below a quarter tank, but before the red light comes on. My gauge tends to be reliable at the top and bottom ends of the needle's travel, but hovers around the middle for too long.

If I'm highway driving I can get to 160 miles (256km) before filling up and that's way before it's empty -- more that I'm nervous about running out and not sure where the next gas station is. I THINK (but won't swear to it) that after a bunch of highway miles and them coming into a city so I wasn't worried, I once got 200 miles (320km) on a tank. The red light came on but the whole tank had been highway cruising.

Your mileage may vary.

Cheers,
phaetn

[spider2081]

My 81 FI gets about 25 MPG average with little highway driving mostly city and back roads. I would expect it to be better if I drove any distance on an interstate. I usually top the tank off after about 220 miles.

[DUCeditor]

Amazing consistency being seen here. My `77 with 122,000 miles on the odometer is still getting a pretty consistent 24 miles per gallon. That on two lane roads almost exclusively -- speed 40 to 60 mph.

I cannot remember the last time I saw the fuel warning light go on. With gas stations sometimes pretty far apart here in rural NH I rarely start a trip of any length with much less than a full tank, and if its below half full I top it off locally before hitting the back roads.

-don