Why Does Fuel Consumption Increase After an Oil Change?

[SanVivienne]

Reasons for increased fuel consumption after an oil change: Higher viscosity of new oil: Over time, used oil deteriorates, leading to a decrease in viscosity, which reduces engine resistance. New oil has higher viscosity compared to the old oil, resulting in perceived increased fuel consumption or reduced power. Insufficient power: This could be due to issues with the car's engine, where the engine lacks sufficient power. Faulty oil filter: If the oil filter is faulty, clogged, or ineffective, it is generally recommended to replace the oil filter along with the new oil. Excessive deposits: If the engine lubrication system hasn't been cleaned for a long time, deposits accumulate. Changing to new oil may dislodge some impurities, suspending them in the oil and clogging the oil filter, leading to insufficient power.