What does the fault mean – and how reliable is the car?

Catalyst system efficiency below threshold, bank 1

Random/multiple cylinder misfire detected

System too lean, bank 1

System too rich, bank 1

EGR A flow insufficient detected

Mass or volume air flow sensor A circuit range/performance

Coolant thermostat (coolant temperature below thermostat regulating temperature)

Turbocharger/supercharger A underboost condition

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