Mazda CX‌-30 Forum banner
21 - 40 of 41 Posts

·
Registered
2021 cx-30 2.5l AWD Turbo premium package
Joined
·
52 Posts
Discussion Starter · #21 ·
How much can you put in to fill from an empty tank?
Haven't allowed myself to run it "dry".

I'll run it out before my next fill up sometime early next week. Can't be too much crap in the tank this early that would clog a filter.
 

·
Registered
'21 CX-30 2.5 Sky G Pref AWD Red
Joined
·
157 Posts
I would never intentionally run mine dry. But the readout gives miles remaining. Low warning goes off at 30 IIRC. So with 20-30 left I get 10.3 to 10.7 gal in.
 

·
Registered
2021 CX-30 2.5L AWD Pearl White
Joined
·
123 Posts
I'm having issues with what appears to be a premature shut off at the pump, leaving me with less than a full tank. I estimate it's a half gallon / gallon short each time.

I'm hesitant to override the shut off mechanism, and risk an overflow.
The risk is the potential damage to the evaporative emissions system when it comes to trying to round up or top off when filling the tank. I saw above that you later said that the fuel gage was showing the tank was under the full level when you fill it. There is a possibility that the sending unit or gage is wrong. When you get low on fuel and the vehicle prompts you to go get some gas, how much does usually get added to the tank by the time it shuts off? Are your fill-ups in the ten gallon range?
 

·
Registered
Current Mazdas: 15 Mazda3, 16 Mazda2, 19 Mazda3 and 3 prior Mazdas
Joined
·
112 Posts
I called Mazda a few years back with my old Mazda3. My question was: when the car is empty is there 3 gallons of gas left in the tank or is there 3 gallons of air when it is full? I was never able to fill it with more than 10 gallons in a 13 gallon tank. (Guessing the capacity a few years later)

They said the tank is not empty when it reads empty. They leave some gas in the tank so you don’t run out and to protect the fuel pump.

I would always buy gas at a quarter tank for the same reasons. Apparently the combination left a half tank.

I would not overfill the tank to avoid back flow into the emission systems (I hope this was not Scotty’s opinion. I would hate to be caught agreeing with him)
 

·
Registered
2021 cx-30 2.5l AWD Turbo premium package
Joined
·
52 Posts
Discussion Starter · #28 ·
The risk is the potential damage to the evaporative emissions system when it comes to trying to round up or top off when filling the tank. I saw above that you later said that the fuel gage was showing the tank was under the full level when you fill it. There is a possibility that the sending unit or gage is wrong. When you get low on fuel and the vehicle prompts you to go get some gas, how much does usually get added to the tank by the time it shuts off? Are your fill-ups in the ten gallon range?
I can't remember the amount of the previous fill-ups, but I will pay attention to the amount of the upcoming one...
 

·
Registered
2021 cx-30 2.5l AWD Turbo premium package
Joined
·
52 Posts
Discussion Starter · #29 ·
I called Mazda a few years back with my old Mazda3. My question was: when the car is empty is there 3 gallons of gas left in the tank or is there 3 gallons of air when it is full? I was never able to fill it with more than 10 gallons in a 13 gallon tank. (Guessing the capacity a few years later)

They said the tank is not empty when it reads empty. They leave some gas in the tank so you don’t run out and to protect the fuel pump.

I would always buy gas at a quarter tank for the same reasons. Apparently the combination left a half tank.

I would not overfill the tank to avoid back flow into the emission systems (I hope this was not Scotty’s opinion. I would hate to be caught agreeing with him)
I was thinking that the manufacturer building in an idiot proof failsafe was a possibility.

Normally I hit the station when the light goes on, and rarely let it get down to one hashmark before "E".

As to Scotty, yeah that's his position as well...heh!

I like Scotty, he makes me laugh.
 

·
Registered
2020 Mazda 3 Premium Hatch polymetal gray over red/blk
Joined
·
222 Posts
It is rather odd that the CX 30 is saddled with a 12.7 (US GAL) tank and that in it's most inefficient form , Turbo awd , has an unusually short range of just 318 miles [ 12.7 x 25 (Combined MPG)].
The 3 turbo with an extra half gallon tank capacity and 2 mpg better Mileage goes a more reasonable 356 miles.
With my N.A 3 hatch 2wd it extends to a pretty decent 382 miles.
 

·
Registered
2021 CX-30 2.5L AWD Pearl White
Joined
·
123 Posts
I would not overfill the tank to avoid back flow into the emission systems (I hope this was not Scotty’s opinion. I would hate to be caught agreeing with him)
Scotty is like the weatherman. They both can be completely wrong and still get paid for their opinions. They can both get it right on occasion. They both can be entertaining enough that many don't even care how often they are wrong and it isn't worth taking the time to correct either of them when they are wrong.
 

·
Registered
2021 cx-30 2.5l AWD Turbo premium package
Joined
·
52 Posts
Discussion Starter · #32 ·
Ok, here we go. The low fuel light came on this morning, so I pulled into my regular gas station for a "fill-up".

2742
2743
2744


Didn't goose the pump. Let it shut off automatically.

And while the fill is better than I've gotten the other two times, it's still a hair short of showing "full".

Being that "hair short" aggravates my OCD, nothing more than that.
 

·
Registered
2021 CX-30 2.5L AWD Pearl White
Joined
·
123 Posts
Being that "hair short" aggravates my OCD, nothing more than that.
It's called parallax. The needle is at the full mark, but since you are looking at it from a higher angle you see part way below it and that makes it appear to be short of the mark.
 

·
Registered
2021 cx-30 2.5l AWD Turbo premium package
Joined
·
52 Posts
Discussion Starter · #34 ·
It's called parallax. The needle is at the full mark, but since you are looking at it from a higher angle you see part way below it and that makes it appear to be short of the mark.
It's a reasonable explanation. Though I seem to remember receiving the beast from the dealership with a "full tank" and that the needle was above that first hashmark.

A couple more fill-ups before I accede to that possibility.
 

·
Registered
2021 CX-30 2.5L AWD Pearl White
Joined
·
123 Posts
Here are two pics of my fuel gage after filling up last night. The reminder system displayed 20 miles remaining, and the fill up was 10.7 gallons. The first pic is taken from a low angle and the needle appears to be well above the full mark.
2754


The second one is from a high angle and it appears to have the needle below the full mark.
2755

This is normal to see this with any gage like this and was a common problem with analog voltmeters. The needle itself isn't moving in these pics..
 

·
Registered
'21 CX-30 2.5 Sky G Pref AWD Red
Joined
·
157 Posts
and was a common problem with analog voltmeters.
Hence the mirrored strip. Reading is good where the needle covers up its reflection.
2756
 

·
Registered
2020 CX-30 GS FWD, Snowflake White
Joined
·
944 Posts
my last fill showed 24 km left on the gauge, filled up to the auto stop on the pump and it took 42.9 litres (my tank size is 51), this is the most I've put in to-date.
 

·
Registered
'21 CX-30 2.5 Sky G Pref AWD Red
Joined
·
157 Posts
I remembered to look at this today. Filled and stopped at self shut-off. Looks perfectly aligned from normal driver view. I actually have my seat adjusted by the way the car tells you to and have no 'comfort issues' like some others have posted.
Speedometer Odometer Motor vehicle Tachometer Gauge
 

·
Registered
2021 cx-30 2.5l AWD Turbo premium package
Joined
·
52 Posts
Discussion Starter · #39 ·
I remembered to look at this today. Filled and stopped at self shut-off. Looks perfectly aligned from normal driver view. I actually have my seat adjusted by the way the car tells you to and have no 'comfort issues' like some others have posted. View attachment 2819
Nice to see.

I'm still hitting anywhere from 1-3 ticks below the full mark. I've only hit the full line once, and that required a couple of gooses of the pump.
 

·
Premium Member
2021 CX-30 S 2.5L white/black
Joined
·
269 Posts
I actually have my seat adjusted by the way the car tells you to and have no 'comfort issues' like some others have posted.
The way the car tells you to? Can you expand on that? Is it in the manual somewhere? Curious and interested to see what it is and how it compares to my seat adjustments.
 
21 - 40 of 41 Posts
Top