Fuel range anomaly

Grateful for any thoughts on this new problem with my car. The last two times I have filled it up the fuel gauge has gone straight to full as usual, however, the range has taken about fifteen miles to rise to the correct mileage. Very strange and I’m assuming it’s not the fuel tank sender as the tank shows full. For some reason the computer takes a while to register the tank is full and to adjust the range possible on that tank. Any experiences of this?

 

The range display is worked out from how much fuel is in the tank and how you have been driving during that journey, or the journey previously.

drive hard for ten miles and your range could drop by 50 miles. Drive gently for 10 miles and the range will increase.

If you suddenly add a load more fuel to the tank The car doesn’t know what to do, so waits a while to make sure the fuel level is accurate, not just sloshing about, or a sensor glitch, and then wants to know how you’re driving for a while before it updates.

it’s only ever a rough estimate anyway, the longer you drive at a constant load the more accurate it becomes, until you fill up again or start driving differently.

 

Thank you. The thing is that something has changed recently. Until a couple of weeks ago when I filled up the range would adjust straightaway, along with the tank level. Now it doesn’t, hence the feeling that something ain’t working as it was.

 

I had exactly the same issue in that they way it worked suddenly changed. In my car after fueling up the range stayed at around 30 miles for around 30 minutes then when it did change went to over 480 miles. Even when it got to half a tank it was still showing 250 miles range.

I am now sure that this was battery related as the car was hardly being used and I was getting battery discharge messages (the battery was replaced 2 months ago and correctly coded). Now, I keep it on a trickle charger and the problem hasn't come back.

 

I'm getting exactly the same thing. I must get round to putting a new battery in.

 

My battery is new and this still happened. It's about ensuring the battery whether new or old is charged (not saying you don't need a new battery as I don't know how old yours is). These cars seem very temperamental to low charge in a number of ways!!

 

I replaced my battery 3 years ago but it has been giving me the bong of death for a few months. I just stick a charger on or go for a drive and it seems OK. However a few weeks ago when I ran the tank really low, it decided that all of a sudden my car could do 40mpg! Its been like this for a while so I have been ignoring it but even if I charge the battery it still does this.

What i have found when I look into the code reader is the IBS thinks the battery is OK for about 5 days and then all of sudden it thinks battery charge is around 27% when I last looked. Charged it up again and the cycle repeats.

 

Thank you, I think you are right so am grateful for the reply. I drove it a 110 miles to a meeting today and filled up when I got there. After filling up the range adjusted straightaway so it must have been battery charge related and after a longer drive it had more charge. So not really a problem. Thanks again

 

yeah, mine must have been similar, 250 miles on half a tank Sounds like your battery is knackered