The Honda Civic from 2017 to 2021 is one of the most popular compact cars in the United States, loved for its reliability, efficiency, and sporty performance. But even the most dependable engines eventually reach their limits, whether due to high mileage, overheating, or mechanical failure. If your Civic needs a new engine, a proper step-by-step approach ensures the replacement is done safely and correctly. At Power Engines, we provide road-legal replacement engines that meet OEM standards, giving you peace of mind when tackling a major project like this.
Preparation and Tools Required
Before beginning, gather the essentials: an engine hoist, hydraulic jack, jack stands, torque wrench, complete metric socket and wrench set, screwdrivers, pliers, drain pans, replacement fluids (engine oil, coolant, transmission fluid), and protective gloves. Always disconnect the battery before working on the car, and ensure the Civic is parked on a level surface.
Step 1: Remove the Hood and Drain Fluids
Unbolt the hood for full access to the engine bay. Drain the engine oil, coolant, and transmission fluid into proper containers. This prevents spills and allows you to start fresh when the new engine is installed.
Step 2: Disconnect Wiring and Fuel Lines
Label all wiring harnesses, sensors, and vacuum hoses for easy reinstallation. Relieve fuel system pressure, then disconnect the fuel lines. Careful labeling and photos during this process make reassembly far easier.
Step 3: Remove Accessories and Cooling System
Detach the alternator, starter motor, power steering pump, and A/C compressor. Where possible, secure them aside in the bay without disconnecting fluid lines. Remove the radiator, cooling fan, and hoses to clear space for engine extraction.
Step 4: Disconnect Exhaust and Transmission
Unbolt the exhaust manifold and catalytic converter from the engine. Support the transmission with a jack or stand, then remove the bolts securing it to the engine block. Automatic Civics require disconnecting torque converter bolts, while manual models involve detaching the clutch assembly.
Step 5: Remove Motor Mounts and Lift the Engine
Unbolt the motor mounts. Attach the engine to the hoist using secure lifting points, then carefully lift it out of the bay. Check that all connections are free to avoid damaging hoses or wiring.
Step 6: Prepare the Replacement Engine
Transfer components such as intake and exhaust manifolds, sensors, brackets, and turbochargers (for Civic Si models) from the old engine to the new one. Always replace gaskets, seals, and belts during this step. Power Engines supplies OEM-spec Honda replacement engines designed to integrate seamlessly with your Civic, ensuring emissions compliance and long-term reliability.
Step 7: Install the New Engine
Lower the replacement engine into the bay with the hoist, aligning it with the transmission and motor mounts. Tighten bolts to manufacturer torque specifications. Reconnect the exhaust, transmission, and all previously removed accessories.
Step 8: Reconnect Wiring, Fuel, and Cooling Systems
Reattach wiring harnesses, fuel lines, and vacuum hoses according to your labels and photos. Reinstall the radiator, hoses, and cooling fan. Fill with fresh fluids—engine oil, coolant, and transmission fluid.
Step 9: Test and Break-In
Reconnect the battery and turn the ignition to ON, allowing the fuel pump to pressurize the system. Start the engine and let it idle, checking for leaks, unusual noises, or warning lights. During the first 500 miles, avoid hard acceleration or high RPMs. Change the oil after the break-in period for maximum engine life.
Replacing the engine in a 2017–2021 Honda Civic may be a detailed and labor-intensive job, but the reward is a refreshed vehicle that’s ready for many more miles of dependable service. Whether you’re driving a base model, turbocharged trim, or a Civic Si, sourcing a quality, road-legal replacement from Power Engines ensures the job is worth the effort. With the right parts and careful step-by-step work, your Honda Civic can continue delivering the performance and reliability it’s famous for.
