How to determine whether your car is consuming excessive fuel?

—— Hong Kong car owner's lazy package | editor teaches you step by step

Hello everyone! Many car owners ask, "Why does my car seem to be consuming less fuel? Is it a problem? What constitutes excessive fuel consumption?" High fuel consumption isn't always a sign of a bad car, nor is it necessarily related to age. Drawing on years of local driving experience, I've broken down some tips for identifying the cause—whether you drive a European, Japanese, or hybrid car, or are a beginner or experienced driver.

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1. What is "Excessive Fuel Consumption"? (Definition)

"Excessive fuel consumption" = Actual fuel consumption is significantly higher than the normal level of the same model/year, or it is significantly worse than your previous driving habits .

example:

• Your Toyota Vios's normal fuel consumption is 5.5-6L/100km (approximately 16-18km/L), but it has recently dropped to 8-10L/100km (approximately 10-12km/L), which is excessive fuel consumption.
• For the same distance and driving mode, the fuel cost suddenly increased by 20% to 30%, which is worth noting.

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2. Simple self-testing fuel consumption steps for Hong Kong car owners

1. Actual measurement method (most accurate)

A. Full oil method

1. Go to the gas station and fill up the tank until the meter automatically jumps (recording the mileage at that time).
2. Drive normally for a period of time (e.g. 200-300 km).
3. Fill up the tank again and record how many liters you put in.
4. Calculated using the formula:
   Fuel consumption (L/100km) = (liters filled/kilometers traveled) x 100

B. Car display method

• Most new cars have an "average fuel consumption" display, but it is for reference only (not necessarily accurate). It is best to verify it every two or three times at a gas station.

2. Refer to online data

• Hong Kong car forums/owner groups : Search for your model + the keyword "fuel consumption" and refer to the actual measured figures of other local car owners.
• Factory data : For reference only. Actual fuel consumption is usually 10-30% higher than official figures.

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3. Common normal fuel consumption range in Hong Kong environment (reference)

Note: Traffic jams, short trips, and running the air conditioner for long periods of time will increase fuel consumption.

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4. How to identify if your car is a "fuel-guzzling" car?

1. Compare yourself to your past

• If you can normally travel 500 kilometers with $500 of gas, but suddenly it can only travel 350-400 kilometers, then your fuel consumption has obviously increased.
• Look back at your fuel costs over the past three months to see if there has been a sudden jump in fuel costs.

2. Compare with other owners of the same model

• Go to the car owner group/forum and ask other people who own the same car to see their average fuel consumption.
• Some cars consume a lot of oil (such as large-displacement, heavy-duty SUVs) and cannot be compared with small cars.

3. Road conditions

• Long-term traffic jams, short trips, and driving with the air conditioner turned up full blast will increase fuel consumption by 20-30%.
• Hong Kong has many traffic lights, slopes and short distances, so high fuel consumption in urban areas is normal.

4. Be careful if your condition suddenly deteriorates

• If fuel consumption increases significantly in a short period of time (for example, it increases by 20% in one month), there is usually a problem.

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5. Common causes of excessive fuel consumption (especially common in Hong Kong)

1. Driving habits

• Prolonged rapid acceleration and braking (especially for novice drivers or those in a hurry)
• The air conditioner is too long when idling (for example, waiting for someone or waiting for parking)
• Frequent heavy loading and trunk full of debris

2. Vehicle maintenance issues

• Insufficient tire pressure : Low tire pressure, high resistance, and significantly increased fuel consumption (it is recommended to check tire pressure every month).
• Filter dirt : The air filter/fuel filter is clogged, resulting in low combustion efficiency.
• Aging of the spark plug : poor ignition efficiency and increased fuel consumption.
• The engine oil is too thick/aged : the engine friction is high and the fuel consumption is high.
• Brakes are stuck/stuck : The brake pads and calipers have not returned to their original positions, resulting in high driving resistance.
• Failure of engine sensors (O2 sensor, MAF) : affects the mixture ratio and causes a sharp increase in fuel consumption.

3. Vehicle mechanical or electronic problems

• Check Engine light is on : There is a problem with the fuel system.
• Automatic transmission failure : transmission slips and fuel consumption soars.
• The air conditioning compressor is overloaded : There is a problem with the air conditioning system, causing the engine to work harder.

4. External influences

• Long-term manned transportation : multiple resistances.
• Installing large rims and wide tires : The tire friction is large.
• Adding heavy parts to the car body (such as roof box, tail spoiler) : air resistance increases.

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6. Editor’s Guide: Judgment & Solution Steps

A. Self-test fuel consumption (perform once for every two cylinders)

• Fill up the tank → record mileage → drive normally → fill up the tank again → calculate fuel consumption
• Note down weather, road conditions, air conditioning usage, etc.

B. Comparison among owners of the same model

• Refer to online forums or car clubs to see if you have any "special"

C. Troubleshooting simple issues

1. Is the tire pressure sufficient? (Check once a month)
2. How long has the air filter/ignition nozzle/engine oil been replaced? (Check every six months/10,000 kilometers)
3. Are there any unusual brake noises or brake drag?
4. Is there a Check Engine light?
5. Is there any "permanent debris" in the trunk?

D. Adopt fuel-efficient driving habits

• Accelerate gently and try to wait until the light turns green before starting.
• Reduce idling time (e.g., turn off the engine when waiting for someone)
• Reduce heavy loads and clean the trunk

E. If all else fails, ask a garage for inspection

• Use computer to diagnose engine sensors and gearbox
• Check the brake and air conditioning systems

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7. Tips on Hong Kong Characteristics

• It is normal for fuel consumption in the city to be higher than on the highway , and sometimes it is not your car's fault.
• Hybrid car owners should pay special attention : battery aging and hybrid system failure will significantly increase fuel consumption.
• Old European cars : Due to their age and poor maintenance, high fuel consumption is inevitable.
• Second-hand or newly purchased car : It is best to make a detailed record of the first few tanks of oil after buying the car.

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8. Editor’s honest opinion: What are some tips for maintaining low fuel consumption?

1. Regular maintenance : Don't be stingy and replace the air filter, tire pressure, and spark plugs according to the recommendations.
2. Develop a record-keeping habit : take a photo of the vehicle and record the mileage every time you refuel for easy tracking.
3. Multi-use Apps : Some fuel consumption recording apps (such as Fuelio and Drivvo) can automatically calculate and analyze.
4. Don’t blindly trust the factory data : Hong Kong has a lot of traffic jams, so the actual fuel consumption must be higher.
5. Don't trust the so-called "fuel-saving tools" on the market : most of them are useless. Maintenance and driving habits are the key.

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9. Editor’s Summary

The easiest way to determine whether your car is consuming excessive fuel is to test, record and compare it yourself!
If any abnormalities are detected, check basic maintenance and driving habits, and compare your data with that of other owners. If high fuel consumption persists despite completing all the above steps, seek further inspection by a professional garage.

Remember: Hong Kong's fuel consumption is relatively high, but with careful record keeping and maintenance, you can save a lot of fuel costs!
If you have any questions, feel free to ask me, I can help you analyze them one by one!