B18U engine — Volvo 1.8 (1.8L)
1.8L · 90 hp
Engine overview
Factory specifications
Values from the manufacturer documentation for this engine.
Engine (general)
| Engine code | B 18 U |
| Capacity | 1794 cc |
| Idle speed | 850 - 950 rpm |
| Inlet | 0.20 ± 0.05 mm |
| Exhaust | 0.40 ± 0.05 mm |
| Normal | 11 - 13 bar |
| Oil pressure | 1.5/1000 bar/rpm |
Engine (petrol)
| Fuel system (make and type) | Fenix 3B |
| Number of cylinders | 4 |
| Firing order | 1-3-4-2 |
| Ignition coil resistance, primary | 0.4 - 0.8 ohms |
| Ignition coil resistance, secondary | 5500-6500 ohms |
| Spark plugs (make and type) | Bosch WR6DC |
| Spark plug gap | 0.7 mm |
| Fuel pump pressure | 2.0-2.5 bar |
| Injection pressure/system pressure | 0.8-1.2 bar |
| CO exhaust gas | < 0.5 % |
| CO2 | 14.5 - 16.0 % |
| HC | 100 ppm |
| O2 | 0.1 - 0.5 % |
| Lambda | 0.97 - 1.03 |
| Oil temperature during test | 70 °C |
| Fast-idle speed | 2400 - 2600 rpm |
| CO at fast-idle speed | < 0.3 % |
| Lambda change (Delta Lambda) | 0.03 |
| Conditioning catalytic converter | 2 / 3000 min/rpm |
Cooling system
| Cap pressure | 1.5 bar |
| Thermostat opens at | 92 °C |
| Fan on at | 95 °C |
Electrical
| Battery | 55 Ah |
| Alternator | 70 A |
Capacities
| Engine sump, incl. filter | 5.3 (-> 1993) 5.0 (1993) 4.6 (1994 ->) l |
| Gearbox refill | 3.4 l |
| Automatic transmission | CVT |
| Gearbox refill | 3.8 l |
| Cooling system | 6.5 l |
Torque settings
| Cylinder head bolts — Stage 1 | 30 Nm |
| Cylinder head bolts — Stage 2 | 70 Nm |
| Cylinder head bolts — Stage 5 | 20 Nm |
| Cylinder head bolts — Stage 6 | 123 ± 2 ° |
| Front hub | 230 Nm |
| Rear hub | 160 Nm |
| Wheel nuts | 110 Nm |
| Spark plugs | 25 Nm |
Workshop procedures for this engine
Step-by-step procedures from the workshop database.
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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.
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The story behind TorqFix →Workshop data on this page last updated 22 Aug 2026.