The Mazda FS-DS is a 1,991 cc, inline‑four naturally aspirated petrol engine produced between 1998 and 2002. It features a cast iron block, aluminium head, and a dual overhead camshaft (DOHC) with four valves per cylinder. Output varied by market, typically rated at 105 kW (143 PS), with torque figures around 180 Nm, enabled by its variable intake manifold (VRIS) for optimized airflow across the rev range.
Fitted primarily to the first-generation Mazda 626 (GF platform) and the Mazda MX-5 (NB), the FS-DS was engineered for responsive, refined performance. Its design prioritised mid-range torque and high-RPM power delivery, making it suitable for sporty sedans and roadsters. Emissions compliance for its era was managed through multi-point fuel injection and basic catalytic converter systems.
One documented concern is premature failure of the variable intake manifold (VRIS) actuators, noted in Mazda Technical Service Bulletin TSB-001-99. This issue, often linked to electrical connector corrosion or actuator motor wear, can cause hesitation, reduced power, and check engine lights. No major generational revisions occurred before the engine was succeeded by the FS-DE variant.
Mazda
Production years 1998–2002 meet applicable Japanese and international emissions standards for their respective model years (VCA UK Type Approval data for imported models).
The Mazda FS-DS is a 1,991 cc inline‑four naturally aspirated petrol engine engineered for sporty sedans and roadsters (1998-2002). It combines a DOHC 16-valve head with a variable intake manifold (VRIS) to deliver strong mid-range torque and high-RPM power. Designed to meet emissions standards of its era, it balances spirited performance with mechanical reliability.
| Parameter | Value | Source |
|---|---|---|
| Displacement | 1,991 cc | |
| Fuel type | Petrol | |
| Configuration | Inline‑4, DOHC, 16‑valve | |
| Aspiration | Naturally Aspirated | |
| Bore × stroke | 86.0 mm × 86.0 mm | |
| Power output | 105 kW (143 PS) | |
| Torque | 180 Nm @ 4,500 rpm | |
| Fuel system | Multi-Point Fuel Injection (MPFI) | |
| Emissions standard | Pre-Euro (Meets 1990s Japanese/US standards) | |
| Compression ratio | 9.7:1 | |
| Cooling system | Water‑cooled | |
| Turbocharger | None | |
| Timing system | Chain-driven DOHC | |
| Oil type | SAE 5W-30 (API SJ or higher) | |
| Dry weight | Not Available |
The DOHC design and VRIS system provide a broad, responsive powerband ideal for spirited driving but require attention to the intake manifold actuators. The VRIS system is prone to failure due to electrical connector corrosion or actuator motor wear, leading to drivability issues. Using the specified SAE 5W-30 oil is critical for optimal lubrication. The timing chain is generally robust but should be inspected for tensioner wear during major services. Regular cleaning of the throttle body and MAF sensor is recommended to maintain optimal air/fuel mixture.
Oil Specs: Requires SAE 5W-30 specification meeting API SJ or higher (Mazda Owner's Manual, 1999).
Emissions: Pre-Euro certification applies to all models (VCA Type Approval data for UK imports). No formal Euro standard existed during its production.
Power Ratings: Measured under JIS or SAE net standards depending on market (Mazda Technical Data Book, 1999).
Mazda Workshop Manual: GF Series 626 (1998-2002)
Mazda Technical Data Book (1999)
Mazda Owner's Manual (1999)
The Mazda FS-DS was used across Mazda's GF sedan and NB roadster platforms with longitudinal mounting. This engine received platform-specific adaptations-different ECU calibrations for the 626 versus the MX-5-and no significant facelift revisions occurred during its production run. All adaptations are documented in OEM technical bulletins.
Locate the engine code stamped on a flat pad on the front of the cylinder block, just below the cylinder head and to the left of the timing cover (Mazda Workshop Manual GF Series). The 8th VIN digit often corresponds to the engine type ('F' for FS series). The FS-DS is visually identified by its DOHC valve cover and the distinctive variable intake manifold (VRIS) assembly on the intake side. The MX-5 (NB) application can be distinguished by its unique intake manifold runners and engine management calibration.
The FS-DS's primary reliability risk is VRIS actuator failure, with elevated incidence in humid or coastal environments. Mazda service data indicates a notable failure rate after 80,000 km, while owner reports frequently cite ignition coil and MAF sensor issues. Infrequent use and poor electrical connections make preventative inspection critical.
Analysis derived from Mazda technical bulletins (1998-2002) and aggregated owner repair data. Repair procedures should follow manufacturer guidelines.
Find answers to most commonly asked questions about MAZDA FS-DS.
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Regulation (EC) No 715/2007
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