Chevrolet S-TEC / Family 0

The small petrol fours of GM's Korean operation — the former Daewoo engines, badged S-TEC and Family 0, in 0.8 to 1.6 litre forms. They power the Spark, Aveo, Cruze and their many rebadged equivalents, and are among the most numerous engines in Eastern Europe, Latin America and Central Asia.

They are simple, belt- or chain-driven, port-injected engines, and the diagnostic profile matches: ignition coils, the crankshaft position sensor, the idle control and vacuum leaks account for most complaints, with few and general codes. Physical testing beats scan data.

The belt-driven versions make the timing belt the item that ends engines, and in the markets where these cars are most common the cars are old and records are thin. As with the Renault K-family, treating unknown belt history as a job due rather than an unknown is the single most valuable piece of advice for this engine.