The automatic climate control system is equipped with sensors. Do not cover or spill any liquid on them.
Honda Civic Owners Manual. Fuel Information
Fuel recommendation
Unleaded gasoline, pump octane number 87 or higher
Use of a lower octane gasoline can cause a persistent, heavy metallic
knocking noise
that can lead to engine damage.
Top tier detergent gasoline
Because the level of detergency and additives in gasoline vary in the market, ...