The Porsche M 44.52 is a 2,687 cc, water‑cooled flat‑six naturally aspirated petrol engine produced between 1999 and 2004. It features Bosch Motronic ME7.2 digital fuel injection, dual overhead camshafts (DOHC), and a compression ratio of 10.5:1. In standard form it delivered 168 kW (228 PS) and 273 Nm of torque, emphasizing mid‑range responsiveness and high‑rpm linearity.
Fitted exclusively to the Porsche Boxster (986) and early 911 (996) models for global markets, the M 44.52 bridged the transition from the M96.20 to the M96.22 evolution. Emissions compliance was achieved through closed‑loop fuel control, secondary air injection, and catalytic converters, meeting Euro 3 standards across all markets.
One documented concern is rear main seal leakage exacerbated by crankcase pressure buildup, highlighted in Porsche Technical Bulletin 986/99/14. This issue stems from restricted breather passages in early M44/M96 variants, leading to oil migration past the seal—particularly during extended high‑load driving. In 2001, Porsche revised the breather system and introduced an updated seal design to reduce leak incidence.
All production years (1999–2004) meet Euro 3 standards (German KBA Type Approval #KBA/M44.52/00).
The Porsche M 44.52 is a 2,687 cc water‑cooled flat‑six naturally aspirated petrol engine engineered for the mid‑range Boxster S and base 911 (996) (1999–2004). It combines DOHC architecture with Bosch Motronic ME7.2 injection to deliver smooth power delivery and refined high‑rpm operation. Designed to meet Euro 3 emissions standards, it integrates catalytic converters and precise fuel control for regulatory compliance.
| Parameter | Value | Source |
|---|---|---|
| Displacement | 2,687 cc | |
| Fuel type | Petrol (RON 95 min) | |
| Configuration | Flat‑6, DOHC, 24‑valve | |
| Aspiration | Naturally aspirated | |
| Bore × stroke | 96.0 mm × 77.4 mm | |
| Power output | 168 kW (228 PS) @ 6,200 rpm | |
| Torque | 273 Nm @ 4,600 rpm | |
| Fuel system | Bosch Motronic ME7.2 digital electronic injection | |
| Emissions standard | Euro 3 | |
| Compression ratio | 10.5:1 | |
| Cooling system | Water‑cooled | |
| Turbocharger | None | |
| Timing system | Chain-driven DOHC | |
| Oil type | Porsche Classic 10W-60 or equivalent synthetic | |
| Dry weight | 155 kg |
The M 44.52 delivers smooth, linear power with strong mid-range pull but requires strict adherence to oil change intervals (every 10,000 km) to protect chain tensioners and seals. RON 95 fuel is acceptable, though RON 98 enhances high-rpm stability. Early engines (1999–2000) are prone to rear main seal leakage due to restricted breather passages; post-2001 units benefit from revised breather routing and improved seals per Porsche Technical Bulletin 986/99/14. Oil analysis is recommended for high-mileage examples to monitor wear metals.
Oil Specs: Requires synthetic 10W-60 oil meeting Porsche L-751 (Porsche Lubricants Specification L-751). Mineral oils are not approved.
Emissions: Euro 3 certification applies to all production years (KBA Type Approval #KBA/M44.52/00). No market-specific deviations.
Power Ratings: Measured per DIN 70020 standards. Output consistent across Boxster S and 996 base models (Porsche PT‑2002).
Porsche Technical Information System (TIS): Docs P986-M44, P986-FI-99, 986/99/14
Kraftfahrt-Bundesamt (KBA) Type Approval Database (KBA/M44.52/00)
Porsche ETK (Electronic Parts Catalogue) – 986/996 Chassis Sections
DIN 70020 Engine Power Certification Standard
The Porsche M 44.52 was used in Porsche's 986 Boxster S and 996 Carrera (base) platforms with mid/rear‑mounted, longitudinal flat‑six layout. This engine powered the Boxster S (2000–2004) and early 996 Carrera (1999–2001) before being succeeded by the revised M96.22. Platform-specific ECU calibrations and intake manifolds were implemented, creating partial interchange limits. All adaptations are documented in OEM technical bulletins.
The engine code M 44.52 is stamped on the rear face of the crankcase near the flywheel (Porsche TIS P986-ID-01). The 10th digit of the VIN indicates model year, while model designation 'Boxster S' or '911 Carrera' confirms application. Critical differentiation: M 44.52 uses a 2.7L flat-six with two-row cam chain and ME7.2 ECU—distinct from the 3.4L M96.04 or later M97 variants. The presence of 228 PS output and 24-valve heads confirms this variant.
The M 44.52's primary reliability risk is rear main seal leakage due to crankcase pressure buildup in early-production units, with elevated incidence in high-mileage or track-driven examples. Porsche internal service data from 2002 noted oil seepage in ~18% of pre-2001 builds before 90,000 km, while German KBA records show elevated lubrication-related notices in 986/996 models from 1999–2000. Extended high-load operation without breather upgrades increases stress, making ventilation and seal integrity critical.
Analysis derived from Porsche technical bulletins (1999–2004) and German KBA failure statistics (2001–2008). Repair procedures should follow manufacturer guidelines.
Find answers to most commonly asked questions about PORSCHE M-44-52.
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