Honda Radiator Cap – 1.1 bar

Honda Radiator Cap

The radiator cap is one of those parts that gets overlooked until the cooling system starts misbehaving. On the 92–01 Civic and 93–97 Del Sol, this is the correct factory-spec cap — manufactured by Toyo for Honda and calibrated to hold 1.1 bar (approximately 16 psi) of system pressure. That pressure rating raises the boiling point of coolant, keeps the system sealed under load, and allows excess pressure to vent to the overflow reservoir rather than pushing past hoses and seals.

A cap that no longer holds rated pressure lets coolant boil at lower temperatures and can push fluid out of the system over time, leading to low coolant levels and gradual overheating — often without an obvious leak. It’s inexpensive insurance on any cooling system service or refresh.

Manufactured to Honda factory specifications for pressure rating, seal geometry, and neck fitment.

Pressure rating: 1.1 bar (110 kPa / ~16 psi) Manufactured by: Toyo

Factory Part Number: 19045-P08-014