Non-linear gas gauge

Wow even in 2022 the gas gauge is still crap?

 

Many cars made in the last ten years or so display range estimates for distance to drive with remaining fuel. My experience is that the estimator starts out with an initial estimate that subsequently changes dependent on the type of driving. It is not unusual to end a drive with a greater range estimate than before it was begun. A very steady moderate speed can vastly increase the estimate compared to aggressive throttle. The estimators use information from a few minutes of driving for each estimate update. This experience is across several manufacturers.

 

Exactly this.

I had this thread in-mind today when I went for a drive into the mountains. I kept an eye on the predicted range and when I got to the top (with lots of wide open throttle & hard acceleration) the remaining range on half a tank was just 110km. On the way down I was much slower in all the tourist traffic (today was a holiday here) and I practically coasted the 2,000m descent. Overall, I covered 150km on the return leg and when I got home the range on 1/4 tank was still 120km. So basically, the range is constantly recalculated on the recent period fuel consumption. Drive hard and it will go down, nanny it and range will go up.

 

My 2010 California barely got 180km’s on tank of gas… the car was on last bar and — lines for range… however, when I filled up, I could only put in around 55 litres… the tank capacity is 78 litres.. so something is up…. Or maybe I wasn’t filling it full? But when I turn on the car, I get full bars of fuel… the both times I filled up, it’s the around the 60 and 55 litres from empty to full…

this car should get at least high 200km in range in city driving… and I wasn’t driving it hard…. Anyone with any input on this? Thanks.

 

That doesn’t sound right to me. 200km on 55l would be nearly 30l/100km or 8mpg. Sounds a bit steep to me. Possible, I suppose, but surely you’d need to be gunning it to use that amount of fuel.

I have a Cali T and easily achieve 15l/100km and at least 350km on a tank, more if it’s highway cruising.

maybe someone with a non turbo Cali can chime in with their experience?

 

Drove less than 15km and lost one bar of fuel... crazy... I wasn't driving it hard at all too... something is not right... either the tank isn't accepting a full tank even though the pump keeps on clicking and the fuel gauge shows full bars... or the sender is faulty...whereby I still have like a quarter of a tank while it thinks it's close to empty... when the car is full, the range indicator shows ~450km... then rapidly drops to mid 200km.. and keeps dropping at a high rate... I don't smell fuel so I don't think I have a fuel leak... runs fine, so it's not running too rich..

Maybe I'll try to fill in more fuel soon and see how much I can put in... Is there a way to reset the fuel gauge? Like pulling a fuse and putting it back in? Does that do anything?

 

Sounds like there’s something wrong. I would say perhaps the fuel gauge sender (float) in the tank is malfunctioning.

If the car is running good, not rich etc. then a relatively easy thing you could do yourself is to brim the tank with fuel, drive 150km, go back to the exact same fuel station/pump and brim the tank again to the same level and then calculate the fuel consumption. If it’s “normal” (let’s say anything around 12-15l/100km) then you know you have an issue with the level sensor.

You can also work out if the gauge is reading properly by noting the level before you refuel and comparing it to the percentage of fuel you add vs. a full tank.

If you’re worried about running out you can always carry a spare 5 litre can.

if the manual fuel consumption calculation checks out then you know you won’t run out of fuel as long as you don’t exceed say, 300km from last full tank and meanwhile you can book the car in to get it checked out properly.

 

The Cali, like many cars, has a saddle tank with two fuel level sender / sensors... perhaps one of them is malfunctioning... I'll check out the wiring to see if there is any connection issues as I only need to take off the rear seats... I'll also do a top up and see how much I can put in and do some calculations... Thanks for the input...

 

Please also take photos when you take out the rear seat and post on here, it will become another good resource. Thanks & hope it’s a simple fix!