Is it better to repair or replace an engine?

The decision to repair or replace an engine requires a comprehensive consideration of the vehicle's condition, the severity of the fault, and the economic cost. For vehicles with a mileage of less than 100,000 kilometres and no history of aggressive driving, if there are localized faults such as piston or valve issues, the repair cost is typically around 30% of a new engine's price, and the repaired engine can still maintain a long service life. Conversely, if the engine has structural damage such as cylinder block cracks or crankshaft failure, or if the vehicle is over 5 years old with repair costs approaching or exceeding 70% of a new engine's price, replacing the complete assembly is more advisable. This is because older vehicles struggle to regain original factory precision after major overhauls, and their subsequent performance and fuel efficiency may be inferior to a new engine. Whichever option is selected, assessment by certified technicians is essential, with preference given to authorised repair facilities or OEM channels to ensure technical reliability and after-sales support. Furthermore, current regulations have eased restrictions on same-model engine replacements and streamlined filing procedures, though cylinder block replacements still require declaration to traffic authorities.