Audi A3 Quattro smell of antifreeze with low fuel rail/system pressure code issue on Audi A3 Quattro

Some Audi A3 Quattro owners report experiencing a smell of antifreeze alongside a low fuel rail/system pressure code issue, such as P0087. This code indicates a problem with achieving sufficient fuel pressure to the fuel rails, which can stem from a weak or faulty high-pressure fuel pump, a clogged fuel filter, or a malfunctioning maximum pressure relief valve. Additionally, the antifreeze smell may be indicative of a separate issue, as leaks in the cooling system—potentially from the radiator, hoses, or water pump—can be mistaken for fuel odors. To accurately diagnose the low fuel pressure issue, owners are advised to check the fuel rail pressure sensor and the low-pressure thrust sensor. It is essential to ensure that the high-pressure pump delivers the required fuel volume and that actual pressure readings align with specifications. Addressing both the fuel system concerns and potential coolant leaks is crucial for resolving these issues effectively.