Question 1

What is the real-world mileage of my car vs ARAI rating?

Accepted Answer

Real-world mileage is typically 15-25% lower than the ARAI-certified figure. ARAI tests are conducted in controlled lab conditions at steady speeds, without air conditioning and with minimal accessories. On Indian roads with city traffic, AC usage, road quality variations, and varied driving patterns, most cars deliver 15-20% less than the stated ARAI figure. A car rated at 20 km/l by ARAI will typically deliver 15-17 km/l in mixed driving.

Question 2

What is good mileage for a car in India?

Accepted Answer

For Indian driving conditions, good mileage is above 15 km/l for petrol cars, above 18 km/l for diesel cars, and above 20 km/l for hybrid vehicles. Average mileage is 10-15 km/l for petrol and 13-18 km/l for diesel. Below 10 km/l for petrol or 13 km/l for diesel is considered poor and may indicate maintenance issues or heavy driving conditions.

Question 3

How do I measure my car actual mileage accurately?

Accepted Answer

The most accurate method is the full-tank method: fill your tank completely, reset the trip meter, drive normally for at least 200-300 km covering your typical route mix (city + highway), then fill up completely again. Divide the distance shown on the trip meter by the litres filled in the second visit. Repeat this 2-3 times and average the results for a reliable real-world mileage figure.

Question 4

Why is my car giving less mileage than expected?

Accepted Answer

Common reasons for poor mileage include: underinflated tyres (5-10% mileage loss), dirty air filter (up to 10% loss), aggressive driving with frequent hard braking (20-30% loss), excessive idling in traffic, running AC at full blast (10-20% loss in small cars), carrying unnecessary weight, and poor quality fuel. A basic service — oil change, air filter, and tyre pressure check — can restore 10-15% of lost mileage.

Question 5

Does AC really reduce mileage?

Accepted Answer

Yes, air conditioning can reduce fuel efficiency by 5-20% depending on the vehicle size and engine. In small cars (800cc-1200cc), AC can reduce mileage by 15-20% in city driving. In larger vehicles (1500cc+), the impact is 5-10%. At highway speeds above 80 km/h, using AC is actually more fuel-efficient than opening windows, which creates aerodynamic drag.

Question 6

Is diesel more fuel efficient than petrol?

Accepted Answer

Yes, diesel engines are 15-25% more fuel efficient than equivalent petrol engines due to higher compression ratios and the greater energy density of diesel fuel. A petrol car giving 15 km/l will typically give 18-20 km/l in its diesel variant. Combined with lower diesel fuel prices, diesel vehicles cost 25-35% less per km to run. However, diesel cars cost more upfront and have higher maintenance costs.

Question 7

How does tyre pressure affect mileage?

Accepted Answer

Underinflated tyres increase rolling resistance, forcing the engine to work harder. For every 5 PSI below the recommended pressure, fuel efficiency drops by about 2-3%. Keeping tyres at the manufacturer-recommended pressure (found on the door jamb sticker or manual) is one of the easiest ways to maintain optimal mileage. Check tyre pressure monthly when tyres are cold, ideally in the morning before driving.

Mileage Calculator India — Check Your Vehicle km/l