Genuine Mazda PCV Valve / Crankcase Breather Valve • L325-13-890A

Genuine Mazda L325-13-890A PCV Valve / Crankcase Breather Valve

Replacement Genuine Mazda positive crankcase ventilation valve for Mazda MX-5 Mk3, Mk3.5 and Mk3.75 NC models fitted with the 1.8-litre L8-VE or 2.0-litre LF-VE petrol engine.

The PCV valve forms part of the engine’s crankcase-breathing and emissions-control system. It regulates the flow of blow-by gases from the crankcase back into the intake system so they can be burned during normal combustion.

On Mazda MX-5 NC applications, the valve is fitted in the engine-block oil separator behind the intake manifold. Although the valve is a small component, access can require removal of the intake manifold and associated hoses or fittings.

During normal engine operation, a small quantity of combustion gas passes the piston rings and enters the crankcase. The PCV system allows these gases and oil vapours to leave the crankcase in a controlled manner while helping maintain suitable internal pressure.

A restricted or stuck PCV valve can contribute to increased crankcase pressure, engine-oil leakage, oil consumption, contamination within the intake system or poor running. A valve that is stuck open may create an unintended intake air path and can contribute to unstable idle or mixture-related running issues.

• Part type: Positive crankcase ventilation valve
• Common names: PCV valve / crankcase breather valve
• Mazda catalogue description: Valve, P.C.V.
• Primary use: Regulates crankcase vapour flow into the engine intake system
• Location on MX-5 NC: Engine-block oil separator behind the intake manifold
• Quantity fitted per engine: 1
• Quantity supplied: 1 PCV valve
• Brand: Genuine Mazda
• Part No.: L325-13-890A
• Also referenced as: L32513890A
• Replaces: LF13-13-890 / LF1313890
• MX-5 fitment: Mk3, Mk3.5 and Mk3.75 NC 1.8 and 2.0 petrol engines

Possible signs of a PCV-system problem:

• Increased crankcase pressure
• Oil seepage from engine seals or gaskets
• Increased oil consumption
• Unstable or rough idle
• Whistling or hissing from the intake or breather system
• Excessive oil contamination inside the intake manifold
• Split, collapsed or oil-softened breather hoses

Fitment advice: This valve is confirmed for all Mazda MX-5 NC 1.8 and 2.0 engine variants. Mazda also uses it on selected Mazda3, Mazda5 and Mazda6 petrol engines. Confirm the original valve reference and engine specification before ordering for wider Mazda applications.

Other items to consider: When replacing the PCV valve, inspect the associated crankcase-breather hoses, oil separator, hose clips, intake-manifold gasket and vacuum connections. Brittle, split, blocked or oil-softened hoses should be replaced where necessary.

Useful tools / consumables: Socket set, extension bars, hose-clamp pliers, torque wrench, intake-safe cleaner, lint-free cloths, replacement intake-manifold gasket where required and suitable hose clips.

Difficulty guide: DIY Difficulty: Moderate to Advanced. The valve itself is straightforward, but its position behind the intake manifold makes access more involved. Care is required when disconnecting aged breather hoses and when refitting the intake manifold and associated vacuum connections.

Why Genuine Mazda? Genuine Mazda PCV valves are designed to provide the original flow-control characteristics, hose connection, sealing arrangement and fit required by the engine’s crankcase-ventilation system. Correct operation is important for maintaining controlled crankcase pressure and reliable emissions-system performance.

What’s in the box: One Genuine Mazda PCV valve / crankcase breather valve, part number L325-13-890A.

Installation notes: Allow the engine to cool before dismantling the intake system. Label and disconnect the necessary hoses and electrical connections, then remove the intake manifold as required for access. Clean the surrounding area before removing the old valve so debris cannot enter the oil separator. Install the new valve securely, inspect all breather hoses and refit the intake components using the applicable Mazda tightening sequence and torque settings. Check for vacuum leaks and correct engine operation after installation.