The ultimate source of power in an engine is the ‘Fuel’. It is burnt inside the engine to generate the heat. This heat is converted into Kinetic Energy by the engine. Although the vehicles have batteries as the secondary power source, they themselves are charged by the current produced using engine’s Kinetic Energy. It means the vehicles are dependent on fuel, directly or indirectly for performing all their functions. The necessity of fuel makes the ‘Fuel Efficiency’ or ‘Mileage’ an important performance parameter. In this post, we will understand the Mileage and the factors on which it depends. We will also look at some techniques for improving it.
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What Is Mileage?
Vehicle Testing On Chassis Dynamometer
Mileage is the parameter which denotes, the distance a vehicle can travel per litre of fuel. It also represents the fuel efficiency of the vehicle. The Mileage generally claimed by the automobile companies is a little bit higher than the actual mileage. This mileage is called ‘Claimed Mileage’ and is measured by Automotive Research Association of India (ARAI). They measure the mileage by conducting tests on Chassis Dynamometers. The vehicles are tested for a 19-minute test cycle. During these cycles, mileage is measured along with other parameters like emissions, acceleration, braking etc.
The actual mileage of vehicles is a bit lesser than the claimed mileage. This is so because of certain factors like:
1. The test is carried out on brand new vehicles only.
2. The real-world driving conditions are completely different from the test conditions.
3. The tests are performed on the Chassis Dynamometers, hence the effect of air drag is completely neglected.
4. The tests do not take in to account, the varying temperature, pressure and altitude conditions.
How Can We Increase The Mileage?
This is the most important and the most sought after question in the field of automotive. The fact is ‘The vehicles can give varying mileage depending upon the driving style and the maintenance. We can increase the mileage of our car by simply improving our driving and maintenance techniques. So, let’s look at all those techniques one by one.
1) Control The RPM of The Vehicle
In Four-Stroke Engines, the fuel is sucked inside the combustion chamber after every two revolutions of the crankshaft. It means a higher number of RPMs means higher fuel consumption. If we unnecessarily increase the RPM of the vehicle, it will cause huge fuel consumption. This situation occurs when we drive our vehicle at high speed in lower gears. We must shift the gears in accordance with the speed of the vehicle. The prescribed ranges of speed are
1st Gear 00 to 10 Km/hr
2nd Gear 10 to 20 Km/hr
3rd Gear 20 to 30 Km/hr
4th Gear 30 to 40 Km/hr
5th Gear 40 Km/hr and above
If you are in 3rd gear and trying to accelerate over the speed of 30 Km/hr, you are causing your engine to revolve at very high speed. This will burn more fuel decreasing the mileage. We must also refrain from driving at lower speeds in top gears. This also puts unnecessary load on the engine, reducing the mileage.
2) Ensure Proper Lubrication
Ensure adequate amount and quality of engine oil in your vehicle. Proper lubrication is very necessary for the functioning of the engine. In case of improper lubrication, the engine components experience more friction and hence engine has to put more efforts in moving them. This increases the load on the engine and causes wastage of energy, which further reduces the mileage. Always use the engine oil prescribed by the manufacturer. Read the owner’s manual to find out the viscosity level of the prescribed engine oil.
3) Refrain from Unnecessary Braking
If you are unnecessarily braking your vehicle, you are causing the loss of power and momentum. The vehicle has to burn extra fuel in order to regain that speed. This reflects in the form of mileage loss. Instead of sudden braking, prefer engine braking if possible. Just release the throttle completely, and let engine braking work.
4) Maintain Proper Tyre Pressure
Ensure that the tyres of your vehicle have proper air pressure. Less air makes the tyres flat, increasing the area of contact between the tyre and the road surface. This increases the friction and put a greater load on the engine. This causes the engine to burn more fuel and hence the mileage decreases. So, to increase the mileage always keep a close look at your tyre pressure.
5) Do Not Keep Your Vehicle Idling At Traffic
Turn off the ignition while you wait on traffic. Doing this will save a considerable amount of fuel. But doing it too often may work other way and may cause more fuel consumption. This is because the vehicle need rich mixture at the time of starting. Turn off your vehicle when you think waiting time would be greater than 30 seconds.
6) Clean Your Air Filters Regularly
Motorcycle Air Filter
The air filters get chocked by the dust particles in the air. This may reduce the air supply to the engine, causing poor combustion. The improper combustion will lead to reduced engine efficiency and hence the mileage will decrease. To avoid this, get your air filters cleaned at regular intervals. Read the owner’s manual to know about the prescribed deadlines. Replace your filters whenever necessary.
7) Close The Car Windows While Driving On Highways
Prefer closing the car’s windows while driving on highways. This is because at higher speeds the air rush inside the cars and opposes its motion. This puts a greater load on the engine, which increases fuel consumption.
8) Park Your Vehicle Under Shades
Petrol and Diesel are highly volatile substances. Parking your vehicle in the sun may cause your fuel to vaporise, reducing the available fuel quantity.
A faulty coolant temperature sensor may give wrong temperature data to the ECU. If the ECU gets lower temperature readings, it will deliver a rich mixture. This will increase fuel consumption, reducing mileage.
10) Clean You Spark Plug Regularly
Carbon deposition on spark plug electrodes may decrease the gap between them. This reduces the intensity of spark and may cause problems like misfiring. All these will lead to poor combustion and hence poor mileage. So, get your spark plug cleaned at regular intervals in order to increase the mileage of your car.
These were a few techniques to increase the mileage of your car. Try out these and let us know if you find them helpful.