The spark plug gap for a 2016 Honda Civic EX is 0.028 inches (0.7 mm) when using the factory-style iridium plugs. If you’re replacing plugs, set them to this gap before installation.
In this article, you’ll find the official gap spec for the 2016 Civic EX, notes on engine/plug variations, and step‑by‑step guidance on how to check and set the gap correctly. We also cover installation tips to help maintain performance and fuel efficiency.
Plug gap specification for the 2016 Civic EX
The 2016 Civic EX uses a 1.5-liter turbocharged engine. The recommended gap for the OEM-style iridium plugs in this configuration is 0.028 inches (0.7 mm). This specification is consistently cited in Honda service information and by major plug manufacturers for the 1.5L turbo setup.
Variations to know
If you are using aftermarket plugs or a different engine variant, the gap can differ. Iridium or platinum plugs intended for the 1.5L turbo commonly maintain a gap around 0.028 inches, but some copper-core or non-OEM plugs may have a different recommended gap. Always verify the exact gap from the plug manufacturer’s packaging or datasheet and follow Honda’s service guidance for your exact engine reference.
How to check and set the gap
Before you start, confirm you are using the correct plug type for your Civic EX. The standard 1.5L turbo configuration typically calls for a 0.028 inch (0.7 mm) gap for OEM-style iridium plugs. If your replacement plugs come pre‑gapped, verify the stated gap on the packaging to ensure it matches 0.028 inches.
- Tools you’ll need: spark plug socket with a ratchet, a torque wrench, a feeler gauge (or a dedicated gap tool), and lubricant/anti-seize as recommended by your plug manufacturer.
- Carefully remove the ignition coil/coil-on-plug assembly and extract the spark plug.
- Measure the gap using a feeler gauge set to 0.028 inches (0.7 mm). If the plug is pre-gapped exactly at 0.028 in, you can proceed without adjustment.
- If adjustment is necessary, do not bend the center electrode or ground electrode aggressively. For iridium plugs, it is generally safer to replace with a correctly pre-gapped plug rather than attempting to re-gap a used plug.
- Install the plug and torque to the recommended specification (typically around 13–15 ft-lbs or 18–20 Nm for 14 mm plugs). Reinstall the coil/boot and ensure a proper seal.
After installation, start the engine to confirm smooth operation. If you notice misfires or rough idle, re-check the gap and torque, and inspect for cross-threading or sealing issues.
Installation tips and care
Using the correct gap is essential for optimal ignition performance, fuel economy, and emissions. Always use plugs that match Honda’s recommended heat range and gap for your engine. When in doubt, consult the owner's manual or a Honda service bulletin for the exact part number and gap specification for your vehicle's build date and region.
Summary
For a 2016 Honda Civic EX, the standard spark plug gap is 0.028 inches (0.7 mm) for the factory iridium plugs used on the 1.5L turbo engine. When replacing plugs, verify and set this gap before installation, torque to the factory specification, and test the engine to ensure proper performance. If you are using aftermarket plugs, always confirm the plug maker’s gap recommendation and ensure it aligns with Honda’s guidance for your engine.