3.3 gas mileage discussion

[MerlintheMad]

that's how I got to 16.2, up to the neck, no spill over.

Costco will roast your butt if you try that and get caught. "No topping off" is a commandment; in quite a few places, actually.

 

[Waynerm002]

Yeah, I know. Don't usually do that at their place but this morning there was barely anyone there, only one car at each station or none so no rush to get it filled.

 

[Stinger GT SS]

Topping off? why such a no no, here in OZ it’s recommends stopping after the pump trigger clicks off, but I always add a couple of bucks more which would fill up to under the overflow in the neck but I’m not aware of “topping off” being such a no no here.
I’d be interested to know why.

 

[MerlintheMad]

As Wayne alluded to: it's rude. Costco gas stations usually have lines waiting. Also, I think some people consider it a hazard; you an get gas flowing down the side of your car.

 

[Stinger GT SS]

As Wayne alluded to: it's rude. Costco gas stations usually have lines waiting. Also, I think some people consider it a hazard; you an get gas flowing down the side of your car.

Thanks @MerlintheMad, ok it’s a courtesy thing, I know you guys have to pay for your petrol before filling so I could see how that could slow down things & yes it can be a hazard & I would never let petrol run down the side of my car.

 

[XZe]

My overall mpg since ive gotten my car, 5700 miles is 18 mpg.
I average basically under 20 daily. I live in SoCal so its constant stop and go traffic.
I fill up on 91 octane.
Its a pain sometimes seeing my gas just disappear lol.

 

[MerlintheMad]

@XZe Yikes! That is horrible. My accumulated data for the last 5691 miles is 22.5 mpg. Not great. But being in Cali made my avg mpg take a further hit (that damned 405); prior to this last trip my average was 23.5. You need to take some road trips to up your mpg!

A lot of my in town driving has been in rush hour evening traffic for c. twelve miles three times per week. But those days are now at an end. With any luck, I should avoid rush hour virtually forever from now on. My accumulated data avg mpg should go up noticeably. But it will take time.

 

[Paul32]

@XZe Yikes! That is horrible. My accumulated data for the last 5691 miles is 22.5 mpg. Not great. But being in Cali made my avg mpg take a further hit (that damned 405); prior to this last trip my average was 23.5. You need to take some road trips to up your mpg!

A lot of my in town driving has been in rush hour evening traffic for c. twelve miles three times per week. But those days are now at an end. With any luck, I should avoid rush hour virtually forever from now on. My accumulated data avg mpg should go up noticeably. But it will take time.

It's how you drive and where you drive. I'm in flat Florida and do not live in town. My overall mileage has been 25.2 mpg, for 5k miles, mid-range gas (89). Only a couple of 200 mile trips one way.

 

[XZe]

@XZe Yikes! That is horrible. My accumulated data for the last 5691 miles is 22.5 mpg. Not great. But being in Cali made my avg mpg take a further hit (that damned 405); prior to this last trip my average was 23.5. You need to take some road trips to up your mpg!

A lot of my in town driving has been in rush hour evening traffic for c. twelve miles three times per week. But those days are now at an end. With any luck, I should avoid rush hour virtually forever from now on. My accumulated data avg mpg should go up noticeably. But it will take time.

I am taking a trip out to vegas at the end of the month. Going to reset my trip counter to see my road trip mpg and see how much it increases my mpg

 

[Paul32]

I am taking a trip out to vegas at the end of the month. Going to reset my trip counter to see my road trip mpg and see how much it increases my mpg

Subtract about 1.5mpg from the computer calculation to get the actual mpg. That's the normal error factor. Every car I have had with a trip computer has been optimistic.

 

[Karl Davlin]

2018, 3.3, AWD - Actual (not the optimistic computer calculation) MPG since the day I purchased it. The lowest point is with 87 octane from the dealer. All others are with 93 octane.

 

[MerlintheMad]

Why is your mileage running backwards? Just curious.

Your average over time is very close to mine.

 

[Mike_TX]

Topping off? why such a no no, here in OZ it’s recommends stopping after the pump trigger clicks off, but I always add a couple of bucks more which would fill up to under the overflow in the neck but I’m not aware of “topping off” being such a no no here.
I’d be interested to know why.

There's a risk of damaging the charcoal filter in the fuel system if you overfill your tank. Google it. Here's one example of the hits:

Damage to the charcoal filter
“By topping your fuel tank off, it can either overwhelm your evaporative system and break something or cause a hazardous leak by the excess pressure in the system,” says Ed Nemphos, owner of Brentwood Automotive in Baltimore.

Topping off your gas tank can cause pressure to build in the tank and flood the carbon filter vapor collection system, only meant for vapor. Subsequently, this overflow can affect your car’s performance and could possibly damage the engine.

“When we overfill the tank, it sends all of the excessive fuel to the evaporation/charcoal canister and kills the life of that canister,” said Joel Carruso of Caruso’s Auto Repair in New York.

Carbon filter canisters cost anywhere from $200 to $1,500 — not to mention the cost of an entire engine!

 

[Karl Davlin]

Why is your mileage running backwards? Just curious.

Your average over time is very close to mine.

I use acar for Android to log. When acar exports to CSV, it goes from the most recent fill up to oldest.