Does your C43 behave the same way?
i fill up my tank when the needle hits the yellow low fuel warning. it will take 13.5 gallons of gas to reach the top to full. i start to drive slow in pure chicago city driving. by the time the gas needle reaches half tank my computer reads that i have drove 130 miles. which to ME that is great since i still have way to go before the gas needle reaches the same point when i filled the car up with gas. BUT, than all of a sudden the gas needle starts to go down very quickly. and i end up with 165-175 total miles by the time i reach the yellow gas warning light.

WHY does the gas guage act like this? from the top (full) i get great mpg. but from half way the gas needle goes down so fast its just nuts. i drive the same way from full to empty so im thinking why why why????

 

The culprits are the shape of the gas tank, the calibration on the float, you're not getting any better or worse mileage - it's just the range of motion of the float w/respect to the potentiometer indicating your level. I always 'zero-out' my odometer, I usually get around 280 miles out of a tank (combined city/highway) or roughly 21 +/- mpg, before the low level indicator light sets off.

 

Thx staplegun. thats such a terrible "design" or whatever the term would be. but thinking about this i believe my bmw 740il did the same thing. as far a mpg with city and highway driving i also do well. but chicago driving is terrible because of the short blocks with stops signs everywhere. but to me the milage on my c43 has been better than all the 6 and 8 cylinders cars i have owned. for me to get 130 miles at half tank was great. the only thing different i have done to my car is i removed the plastic air ducts on the front and replaced it with clothes dryer hoses to fit in FRONT of the grille. this helped to the air to come in quicker like forced air. the performance is great with this simple mod. i thought it would hurt mpg but it has made it better.

thanks for the help.

 

Btw, i dont want to start another thread so i like to ask this here. do any of you guys have "mud guards" on your c36-43? any pictures available on the forum or internet tha you know of? i want to see how they look on the car before making a purchase.

i just bought and installed the akebono brake pads and now my wheels stay very clean! now i want to keep the bottom of my car as clean as possible as well. i know thw mud guards will help alot but i dont want he cat to look funny or ugly.

thx.

 

It is the same in most vehicles.... My Saab, Jeep, audi did the same thing, these indicators are not very accurate all the time. It looks awesome when you fill it up, and once at half tank, it looks like car sucks more gas...But like staple said, you are not losing anything....

I get 330 miles average per tank..

 

Sounds like every gas gauge on every car I have owned, but one. The Volvo is the only car I have ever had where it was almost 1:1 on needle movage vs. gas consumption.