Mazda 5 reserve fuel tank

[hyun_sg]

Hi all, I have an April 2015 Mazda 5 Skyactive 2.0L which has a 60L fuel tank according to the manual.
However, after all the fuel indicator bars have disappeared and I'm out of gas according to the display (available Range reported as 0 km on the trip computer) I can only pump 48.8L more before I hit full tank.

That would mean it's a large reserve tank of about 10 litres, never owned something with such a large reserve before so I'm quite surprised.
My Mazda dealership is too lazy & refuses to verify this fact with Mazda headquarters even though they admit they don't know the answer, so I'm checking with you guys, what do you think?

Thanks !

 

[Orangutan]

There's no reserve tank. The trip computer and fuel gauge are simply very conservative. They want you to think you're out of gas before you actually run completely out. My fuel tank (60l is about 15ish gallons, which is what the tank in the U.S. is) is the same way. I get a fuel warning, fill up, and put about 13 gallons (49ish liters) in.

 

[Secondtyme]

If you stop fueling the car when the pump automatically shuts off, you will NEVER get a full tank of gas. I top off every single time I fill up and have added anywhere between two and almost five gallons of fuel to the tank after the pump auto-stops. Its the damned EPA, trying to control evaporative emissions at the pumping stations thats to blame. There I'm taking off my tin-foil baseball cap now LOL

 

[thaxman]

Reported tank capacity is 15.9 gal (US), which is a hair over 60L. In my experience, the low-fuel light consistantly comes on when there is a good 3+ gal left in the tank. I know I can drive another 30-40 mi city before I even need to think about finding a station, so I can wait a day or 2. And even then, I typically can only fit 13.5-14.5 gal in the tank. This really messes with the "total range" figure many car mags like to report, since panic will set in although you still have many many miles left to travel.

 

[underconstructi]

If you stop fueling the car when the pump automatically shuts off, you will NEVER get a full tank of gas. I top off every single time I fill up and have added anywhere between two and almost five gallons of fuel to the tank after the pump auto-stops. Its the damned EPA, trying to control evaporative emissions at the pumping stations thats to blame. There I'm taking off my tin-foil baseball cap now LOL

Its full when the pump clicks.

Continuing to pump can cause fuel to enter the evap system and may saturate the charcoal canister with fuel. This will set a check engine light... and a replacement charcoal canister... not worth the lil bit of extra fuel imho

 

[Secondtyme]

While I'm sure that is the case in some situations (adding fuel until it runs out the side of the car for example) It is absolutely not true in every situation. When I am showing an empty tank, fuel light on, range at 415 miles, I will put 14.5-15.3 gallons in the tank to fill it. The pump cuts off automatically at 10.5 gallons! What, does fuel expand like A-B foam in certain locations? I have topped off my Subaru for 10 years in this fashion and at 264K The charcoal canister is JUST FINE...

 

[thaxman]

From experience, you can pretty much always ad a minimum of a half-gallon after the pump shuts off w/o worrying about the evap system. Now trying to shove 4 extra gallons in it after driving 20+ mi with the gas light on...that will flood the evap for sure. Use some sense and you'll be fine.

 

[SonicBoy]

They always advise to have at least half tank of gas as it aids in keeping the fuel pump cool while in use.

It's also advised in colder climates to avoid having ice form in the tank.

 

[MZ5black]

I've never been on low in my '14MY in terms of seeing the warning indicator. Prefer to keep quarter tank of fuel (according to the display) at all times. The lowest was about two "bars" -- one below quarter tank. At that point I added 12.5 or so gallons (about 47 liters). Filled up until the automatic shut-off and didn't top it off. Pretty sure that was either full tank or very close to full. Pre-2012 cars may be different.

 

[FiftySix]

They always advise to have at least half tank of gas as it aids in keeping the fuel pump cool while in use.

It's also advised in colder climates to avoid having ice form in the tank.

I've always been told 1/4 tank in regards to fuel pumps.

Down here in Texas, I've been told that a full tank of gas helps prevent water condensation from happening internally but that is a bigger worry in aircraft here than cars.