Why does my Suzuki Swift lose fuel efficiency without any warning lights?

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Why does my Suzuki Swift lose fuel efficiency without any warning lights?

My Suzuki Swift’s mileage has ped significantly, but there are no dashboard warning lights. Could a minor fuel leak, damaged fuel injector, o r a loose fuel cap be the cause? What are common fuel system problems in Swift that reduce efficiency silently?

Gari Specialist asked on 02 May 2025 17:42:05 pm

1 Answer

16 views |

Gari Master - on 02 May 2025 17:44:53 pm

A in mileage without dashboard alerts could be due to a minor leak, evaporation losses, o r a malfunctioning fuel injector o r O2 sensor—which may not trigger a warning immediately.

Common Causes:

Loose fuel cap causing fuel vapor to escape.

Cracked o r leaky fuel lines resulting in minor unnoticeable fuel loss.

Clogged o r leaking injectors, leading to inefficient combustion.

Failing oxygen O2 sensor giving wrong fuel-air mix data.

Driving habits o r low tire pressure, which also impact mileage.

Fixes:

Replace o r tighten the fuel cap and monitor smell o r pressure loss.

Have a mechanic perform a fuel pressure and leak-down test.

Clean o r replace fuel injectors and O2 sensors, if required.

Check tire pressure and air filter, as these also affect fuel economy.