2.5L I4 Skyactiv-G Engine Assembly with Cylinder Deactivation for 2021-2024 Mazda

A quick look at your own vehicle makes sure the right engine shows up:

• Verify the 8th digit of the VIN is 'M'.
• Confirm whether the vehicle is FWD or AWD.
• Visually confirm the engine is naturally aspirated (no turbocharger plumbing).

What the install really takes — plan and budget with confidence:

Special tools this job needs:

• Engine hoist/crane and load leveler
• Engine lift table with specialized attachments (e.g., Mazda tool PLA-15)
• High-precision digital torque wrench
• Fuel line disconnect tools
• Mazda-compatible diagnostic scan tool (FORScan, Mazda IDS, or MDARS)

Budget for these consumables at install:

• 0W-20 full synthetic engine oil (approx. 4.8 quarts)
• Genuine Mazda SkyActiv oil filter (or high-micron equivalent)
• Mazda FL-22 long-life pre-diluted engine coolant
• New OEM-spec NGK Iridium spark plugs (e.g., NGK ILKAR7L11)
• New intake manifold gasket set
• New exhaust manifold gasket
• New oil pan drain plug crush washer
• New O-rings for the thermostat and Coolant Control Valve
• High-quality grey RTV silicone sealant
• New serpentine/drive belt

What your vehicle’s computers will need after the swap:

What’s involved: Crankshaft Position (CKP) sensor relearn, throttle body idle air volume learning, clearing adaptive transmission values, and immobilizer/security system synchronization.

sources differ: Arm 1 states no ECU remarriage is required but a CKP relearn is mandatory via FORScan/IDS. Arm 2 states an immobilizer/security system re-sync is required with the vehicle's ECU/PCM using MDARS to prevent a no-start condition — confirm with us before install

Pro tips for a smooth first start-up — hand them to whoever does the install:

• AWD vs. FWD Oil Pan and Pickup Tube Transfer: If swapping between AWD and FWD donor/recipient, you must swap the original oil pan and internal oil pump pickup tube to clear the transfer case.
• Cylinder Deactivation Solenoid Inspection: Inspect solenoids and oil control valves on the cylinder head for clogging or metal debris before installation.
• Fragile High-Pressure Fuel System: Relieve fuel system pressure before disconnecting. High-pressure fuel lines use single-use crush seals and must be replaced.
• Torque-to-Yield Crankshaft Bolt: The crankshaft pulley bolt is a TTY fastener and must be replaced with a new OEM bolt if removed.
• Supporting the Engine Safely: Never place a floor jack directly under the aluminum oil pan; use an engine hanger or specialized lift table.
• Engine/Transaxle Removal: Factory procedure requires removing the engine and transaxle together from underneath the vehicle.
• Ground Straps: Ensure all engine and chassis ground straps are properly connected to avoid electronic issues.

Easy to get right once you know them:

• Buying for a Non-Cylinder Deactivation Vehicle (VIN L or A instead of VIN M).
• Attempting to use the donor vehicle's ECU/PCM, which triggers the immobilizer system.
• Reusing high-pressure direct-injection fuel lines, leading to fuel leaks.
• Skipping the Crankshaft Position (CKP) sensor relearn or security sync.
• Using incorrect engine oil viscosity (non-0W-20) or low-quality oil filters.

Not issues with the units on this page — the manufacturer documented these for every engine of this family, wherever you buy one. Handy for your installer: