Z20DMH engine — Opel 2.0 CDTI (2L)
2L · 125-150 hp
Engine overview
Vehicles with this engine
Factory specifications
Values from the manufacturer documentation for this engine.
Engine (general)
| Engine code | Z 20 DMH |
| Capacity | 1991 cc |
| Idle speed | 840 ± 20 rpm |
| Normal | 26.0 bar |
| Max. compression loss between cylinders | 10 % |
Engine (diesel)
| System (make and type) | Bosch EDC 16C39 |
| Number of cylinders | 4 |
| Injector firing order | 1-3-4-2 |
| Pressure | < 1600 bar |
| Pressure | 4.2 - 5.4 bar |
| Maximum rail pressure | 1600 bar |
Cooling system
| Cap pressure | 1.4 bar |
| Thermostat opens at | 80 ± 2 °C |
| Thermostat fully open at | 95 °C |
| Stage 1/Fan 1 | 100 °C |
| Stage 2/Fan 2 | 105 °C |
Electrical
| Battery | 90 Ah |
| Alternator | 125 A |
Capacities
| Engine sump, incl. filter | 6.2 l |
| Manual transmission | GMDAT D33 |
| Gearbox refill | 2.1 l |
| Gearbox refill | 2.3 l |
| Automatic transmission | Aisin AW55-51LE |
| Initial filling | 7.11 ± 0.15 l |
| Gearbox refill | 2.5 l |
| Transfer box | 0.8 ± 0.1 l |
| Differential, 4WD rear | 0.6 ± 0.1 l |
| Cooling system | 9.0 l |
| Power steering | 1.1 l |
| Air-conditioner refrigerant | 520 ± 20 g |
| Air-conditioner compressor oil | 150 ml |
Torque settings
| Cylinder head bolts — Stage 1 | 65 Nm |
| Cylinder head bolts — Stage 2 | 120 ° |
| Cylinder head bolts — Stage 3 | 120 ° |
| Big-end bearing cap — Stage 1 | 25 Nm |
| Big-end bearing cap — Stage 2 | 90 ° |
| Inlet manifold | 16 Nm |
| Exhaust manifold | 33 Nm |
| Glow plugs | 10 Nm |
| Crankshaft pulley | 34 Nm |
| Flywheel | 105 Nm |
| Alternator | 30 Nm |
| Starter motor | 45 Nm |
| Crankshaft gearwheel | 235 Nm |
| Wheel nuts | 125 Nm |
| Front hub | 205 Nm |
| Rear hub | 205 Nm |
Workshop procedures for this engine
Step-by-step procedures from the workshop database.
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Get free diagnosis →Who makes these pages, and how
TorqFix was built by a mechanic — after a 2,700 km drive with five roadside repairs that no diagnostic tool could explain.
The figures on this page come from manufacturer workshop documentation and are shown as they are. The page is assembled automatically from that data — it is not written by an AI. The AI works in the chat, where it answers for your specific car. It writes nothing here.
Variants of the same model differ. Cross-check torque against the factory manual for your engine before final tightening.
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The story behind TorqFix →Workshop data on this page last updated 22 Aug 2026.