2012-2015 Honda Civic Si 2.4L Inline-4 DOHC i-VTEC Engine JDM K24A

About this unit

Vehicle Fitment

This engine serves as a direct long-block replacement for the following North American models:

• Honda Civic Si (Coupe & Sedan): 2012, 2013, 2014, 2015

• Compatibility Note: While the JDM K24A block is physically compatible, you must transfer your original USDM external components (manifolds, sensors, and harness) to ensure 100% plug-and-play functionality with your Civic Si’s factory ECU and emissions system.

JDM to USDM Installation & Swap Guide

To ensure 100% compatibility and maintain your Civic Si’s performance and emissions status, professional technicians recommend the following “External Swap” steps:

1. Intake & Exhaust Manifolds: You must transfer your original USDM Intake Manifold and Exhaust Manifold. JDM versions may have different vacuum port layouts and lack specific sensors required for North American OBDII compliance.

2. Wiring Harness: Always retain and use your original USDM Engine Wiring Harness. JDM harnesses are configured for right-hand drive (RHD) and will not interface with your Civic’s chassis bulkheads or ECU location.

3. Engine Sensors: Transfer your original USDM Camshaft, Crankshaft, and VTEC Sensors. Honda electronics are highly sensitive; using your original “known-good” sensors prevents intermittent signal issues or Check Engine Light codes.

4. VTC Actuator: We recommend inspecting your original VTC actuator. If it was not rattling on cold starts, transfer it, or install a new updated OEM Honda VTC Actuator while the engine is out to prevent the common cold-start “grind” common to the K-series.

5. Coolant Housing: Utilize your original USDM water housing to ensure the coolant temperature sensors and hose locations match your factory cooling system perfectly.

What is included

You receive exactly what is pictured. Engines are supplied as a long block assembly with the components visible in the photos. Accessories such as the alternator, starter, intake manifold or sensors are included only where you can see them on the unit, so check the photographs before ordering and ask us if anything is unclear.

Before you order

• Confirm the engine code against your own vehicle, not just the model year.
• Japanese market units can differ from the US version in intake, loom and sensors.
• Replace the timing components, water pump and seals while the unit is out. It is cheap insurance on an engine this age.
• Keep your original accessories until the swap is finished and running.