Post Your Average Fuel Consumption [Merged]

**desertst0rm** · November 28th, 2016 06:56 AM

Originally Posted by jut703

Galing naman, all the car manufacturers in the world with billions of dollars of R&D couldn't think of that.

Also odd because whether I fill up my Mazda 3 with 3/4 left in the tank or with 1/4 left in the tank, my mileage is still the same at 5-6 km/L for city driving. Hindi naman electronic throttle yun.

You know what improves my FC to 12 km/L? Driving on the highway. [emoji12]

Sent from my iPhone using Tapatalk

WHAT? They are spending billions on advertising to convince people that their newer model of vehicles are getting more fuel efficient, more safe and more environment friendly even though they're not.

"If you tell a big enough lie and tell it frequently enough, it will be believed."

According to EPA Evaporative emissions occur several ways: https://nepis.epa.gov/Exe/ZyPDF.cgi/...y=P10001KF.PDF

DIURNAL: Gasoline EVAPORATION INCREASES as the TEMPERATURE RISES during the day, HEATING the FUEL TANK and venting gasoline vapors.
RUNNING LOSSES: The hot engine and EXHAUST SYSTEM can vaporize gasoline when the car is running.

HOT SOAK: The ENGINE REMAINS HOT for a period of time after the CAR IS TURNED OFF, and GASOLINE EVAPORATION CONTINUES when the CAR IS PARKED.

REFUELING: Gasoline vapors are always present in fuel tanks. These vapors are forced out when the tank is filled with liquid fuel.

PERMEATION emissions are specific hydrocarbon compounds that escape through micro-pores in pipes, fittings, fuel tanks, and other vehicle components (typically made of PLASTIC or RUBBER). They differ from leaks in that they occur on the molecular level and do not represent a mechanical/material failure in a specific location. https://nepis.epa.gov/Exe/ZyPDF.cgi?Dockey=P100KB5V.pdf

Pano mo compute ang fuel consumption kung di mo alam exact volume ng fuel tapos estimated lang din yung natirang fuel? Matakaw talaga pag within 15-85% fuel level dahil ng EVAP tapos return type fuel system. Pero from full hanggang 85% napakatipid. Mas malakas pa sa gas 2012 CRV ko kesa sa F150 4.2 V6 OHV at E150 na 4.6 V8. Malaki at mabigat pa rim ng CRV (17") kesa sa 98 F150 (16") at E150 (15").

**dr. d** · November 28th, 2016 09:04 AM

aren't the vapor pressure and rate of evaporation the same, whether the tank is 15% full or 85% full?

**oj88** · November 28th, 2016 01:00 PM

Originally Posted by desertst0rm

WHAT? They are spending billions on advertising to convince people that their newer model of vehicles are getting more fuel efficient, more safe and more environment friendly even though they're not.

Your post is riddled with inaccuracies and partial-truths. Allow me the pleasure of a rebuttal.

Let's stick to facts and simple physics... Newer vehicles are built with lighter materials, employing tighter engine tolerances, more efficient transmission gearing, and closed-looped, computer-controlled ignition systems that delivers precise fuel and air quantity as required, among many others. Why would you say that newer [internal combustion] cars are NOT more fuel efficient compared to older [internal combustion] vehicles?

Don't get me started on 'safety', as that is a different topic altogether.

IURNAL: Gasoline EVAPORATION INCREASES as the TEMPERATURE RISES during the day, HEATING the FUEL TANK and venting gasoline vapors.

RUNNING LOSSES: The hot engine and EXHAUST SYSTEM can vaporize gasoline when the car is running.

There's this thing called the Evaporative Canister or EVAP (Controlling Emissions - How Evaporative Emission Control Systems Work | HowStuffWorks), which you briefly mentioned but I'm not sure you understand how it works. As the fuel in the tank generates vapors due to elevated heat or as a result of fuel sloshing around, the EVAP (charcoal) canister absorbs the vapors for temporary storage. Two ways these vapors are released; First, when the fuel tank temperature cools down, the vapors in the tank contract and pulls the stored vapor from the EVAP canister. Second, the collected vapors are purged every now and then by the ECU and sent to be burned by the engine. As required by environmental laws, raw fuel vapors ARE NEVER vented into the atmosphere.

Additionally, modern vehicles have a 'closed' fuel system. In fact, while the engine is running, the fuel tank is maintained at a slight negative pressure (vacuum). If there's a leak (ie. faulty EVAP, loose or faulty fuel filler cap, etc.), a vacuum will never happen, tripping a pressure sensor and sending a Check Engine Light to the driver while a DTC is triggered (P452 EVAP System Pressure Sensor/Switch Low DTC)

HOT SOAK: The ENGINE REMAINS HOT for a period of time after the CAR IS TURNED OFF, and GASOLINE EVAPORATION CONTINUES when the CAR IS PARKED.

That was true with carbureted engines of old (open throat with float tank, technically exposed, etc.) NOT so with modern EFI engines with a closed fuel system.

REFUELING: Gasoline vapors are always present in fuel tanks. These vapors are forced out when the tank is filled with liquid fuel.

True, but you'll have to blame the government for that. The fact is, fuel pumps in more progrssive nations have a vapor recovery system to prevent displaced vapors from venting into the atmosphere (https://www.google.com/url?sa=t&rct=...95yajg&cad=rja)

PERMEATION emissions are specific hydrocarbon compounds that escape through micro-pores in pipes, fittings, fuel tanks, and other vehicle components (typically made of PLASTIC or RUBBER). They differ from leaks in that they occur on the molecular level and do not represent a mechanical/material failure in a specific location.

Again, true, but not really a serious problem. We're talking about tinier than trace amounts of fuel getting through. In the context of fuel economy, fuel loss in this manner is practically considered negligible. In my own guesstimation, we're probably talking micro-liters of lost fuel due to permeation in a span of years... or even the whole life of the vehicle.

**desertst0rm** · December 3rd, 2016 06:47 AM

Originally Posted by oj88

Your post is riddled with inaccuracies and partial-truths. Allow me the pleasure of a rebuttal.

Let's stick to facts and simple physics... Newer vehicles are built with lighter materials, employing tighter engine tolerances, more efficient transmission gearing, and closed-looped, computer-controlled ignition systems that delivers precise fuel and air quantity as required, among many others. Why would you say that newer [internal combustion] cars are NOT more fuel efficient compared to older [internal combustion] vehicles?

Don't get me started on 'safety', as that is a different topic altogether.

There's this thing called the Evaporative Canister or EVAP (Controlling Emissions - How Evaporative Emission Control Systems Work | HowStuffWorks), which you briefly mentioned but I'm not sure you understand how it works. As the fuel in the tank generates vapors due to elevated heat or as a result of fuel sloshing around, the EVAP (charcoal) canister absorbs the vapors for temporary storage. Two ways these vapors are released; First, when the fuel tank temperature cools down, the vapors in the tank contract and pulls the stored vapor from the EVAP canister. Second, the collected vapors are purged every now and then by the ECU and sent to be burned by the engine. As required by environmental laws, raw fuel vapors ARE NEVER vented into the atmosphere.

Additionally, modern vehicles have a 'closed' fuel system. In fact, while the engine is running, the fuel tank is maintained at a slight negative pressure (vacuum). If there's a leak (ie. faulty EVAP, loose or faulty fuel filler cap, etc.), a vacuum will never happen, tripping a pressure sensor and sending a Check Engine Light to the driver while a DTC is triggered (P�452 EVAP System Pressure Sensor/Switch Low DTC)

That was true with carbureted engines of old (open throat with float tank, technically exposed, etc.) NOT so with modern EFI engines with a closed fuel system.

True, but you'll have to blame the government for that. The fact is, fuel pumps in more progrssive nations have a vapor recovery system to prevent displaced vapors from venting into the atmosphere (https://www.google.com/url?sa=t&rct=...95yajg&cad=rja)

Again, true, but not really a serious problem. We're talking about tinier than trace amounts of fuel getting through. In the context of fuel economy, fuel loss in this manner is practically considered negligible. In my own guesstimation, we're probably talking micro-liters of lost fuel due to permeation in a span of years... or even the whole life of the vehicle.

Originally Posted by oj88

Your post is riddled with inaccuracies and partial-truths. Allow me the pleasure of a rebuttal.

Let's stick to facts and simple physics... Newer vehicles are built with lighter materials, employing tighter engine tolerances, more efficient transmission gearing, and closed-looped, computer-controlled ignition systems that delivers precise fuel and air quantity as required, among many others. Why would you say that newer [internal combustion] cars are NOT more fuel efficient compared to older [internal combustion] vehicles?

Don't get me started on 'safety', as that is a different topic altogether.

There's this thing called the Evaporative Canister or EVAP (Controlling Emissions - How Evaporative Emission Control Systems Work | HowStuffWorks), which you briefly mentioned but I'm not sure you understand how it works. As the fuel in the tank generates vapors due to elevated heat or as a result of fuel sloshing around, the EVAP (charcoal) canister absorbs the vapors for temporary storage. Two ways these vapors are released; First, when the fuel tank temperature cools down, the vapors in the tank contract and pulls the stored vapor from the EVAP canister. Second, the collected vapors are purged every now and then by the ECU and sent to be burned by the engine. As required by environmental laws, raw fuel vapors ARE NEVER vented into the atmosphere.

Additionally, modern vehicles have a 'closed' fuel system. In fact, while the engine is running, the fuel tank is maintained at a slight negative pressure (vacuum). If there's a leak (ie. faulty EVAP, loose or faulty fuel filler cap, etc.), a vacuum will never happen, tripping a pressure sensor and sending a Check Engine Light to the driver while a DTC is triggered (P�452 EVAP System Pressure Sensor/Switch Low DTC)

That was true with carbureted engines of old (open throat with float tank, technically exposed, etc.) NOT so with modern EFI engines with a closed fuel system.

True, but you'll have to blame the government for that. The fact is, fuel pumps in more progrssive nations have a vapor recovery system to prevent displaced vapors from venting into the atmosphere (https://www.google.com/url?sa=t&rct=...95yajg&cad=rja)

Again, true, but not really a serious problem. We're talking about tinier than trace amounts of fuel getting through. In the context of fuel economy, fuel loss in this manner is practically considered negligible. In my own guesstimation, we're probably talking micro-liters of lost fuel due to permeation in a span of years... or even the whole life of the vehicle.

What? Puro naman FICTION mga pinagsasabi mol
Almost everything about EVAP, EGR and Vapor Canister are lies. May vent ang fuel tank. Kaya nag auautomatic shut off yung nozzle ng gas station hindi dahil puno na ang tank kundi dahil naharangan na ng liquid yung vapor vent. Gasoline Volumetric Expansion rate is 4x more greater than water. The Fuel Cap relieves excess pressure (2 PSI)& vacuum build up in the fuel tank. Ano ba tawag mo sa mga magkakatabing pipe na mataas sa gas station?

Permeation is not serious problem if your fuel tank is made of metal. Made of plastic na kaya mga fuel tank ngayon.

**desertst0rm** · December 13th, 2016 03:53 AM

Originally Posted by oj88

There's this thing called the Evaporative Canister or EVAP (Controlling Emissions - How Evaporative Emission Control Systems Work | HowStuffWorks), which you briefly mentioned but I'm not sure you understand how it works. As the fuel in the tank generates vapors due to elevated heat or as a result of fuel sloshing around, the EVAP (charcoal) canister absorbs the vapors for temporary storage. Two ways these vapors are released; First, when the fuel tank temperature cools down, the vapors in the tank contract and pulls the stored vapor from the EVAP canister. Second, the collected vapors are purged every now and then by the ECU and sent to be burned by the engine. As required by environmental laws, raw fuel vapors ARE NEVER vented into the atmosphere.

True, but you'll have to blame the government for that. The fact is, fuel pumps in more progrssive nations have a vapor recovery system to prevent displaced vapors from venting into the atmosphere.

Again, true, but not really a serious problem. We're talking about tinier than trace amounts of fuel getting through. In the context of fuel economy, fuel loss in this manner is practically considered negligible. In my own guesstimation, we're probably talking micro-liters of lost fuel due to permeation in a span of years... or even the whole life of the vehicle.

What serious problem?
Hydrocarbon can be extracted from air.
co2 disolves in water.

Do you know what's the real reason why plastics were banned worldwide? Because it can be converted to oil.