OPEL / VAUXHALL C18NZ — 1.8L Engine
1.8L · 90 hp
Engine overview
Vehicles with this engine
Factory specifications
Values from the manufacturer documentation for this engine.
Engine (general)
| Engine code | C18NZ |
| Capacity | 1796 cc |
| Idle speed | 820 - 980 rpm |
| Automatic | 750 - 910 rpm |
| Oil pressure | 1.5/820 - 980 bar/rpm |
| Engine code | C 18NZ |
| Idle speed | 800 - 960 rpm |
| Normal | 9.2 bar |
| Oil pressure | 1.5/880 bar/rpm |
Engine (petrol)
| Fuel system (make and type) | Rochester Multec |
| Number of cylinders | 4 |
| Firing order | 1-3-4-2 |
| Ignition coil resistance, primary | 0.3 - 0.6 ohms |
| Ignition coil resistance, secondary | 7000 - 8400 ohms |
| Spark plugs (make and type) | AC Delco ACCR42LXS |
| Spark plug gap | 0.7 - 0.8 mm |
| Fuel pump pressure | 3.0 bar |
| Injection pressure/system pressure | 0.76 bar |
| CO exhaust gas | < 0.5 % |
| CO2 | 14.5 - 16 % |
| HC | 50 ppm |
| O2 | 0.1 - 0.5 % |
| CO at fast-idle speed | < 0.3 % |
| Fast-idle speed | 2800 - 3200 rpm |
| Lambda | 0.97-1.03 |
| Oil temperature during test | 80 °C |
| Closed-loop test at: | 720 - 1080 rpm |
| Closed-loop test at: | 550 - 910 rpm |
| Timing stroboscopic (before TDC) | 10/880 °/rpm |
| Ignition coil resistance, primary | 0.68 - 0.76 ohms |
| Spark plugs (make and type) | Bosch FR8LDC |
| Lambda | 0.97 - 1.03 |
| Closed-loop test at: | 700 - 1060 rpm |
| Closed-loop test at: | 650 - 1010 rpm |
Cooling system
| Cap pressure | 1.2 - 1.5 bar |
| Thermostat opens at | 92 °C |
| Fan on at | 100 °C |
| Cap pressure | 1.20 - 1.35 bar |
Electrical
| Battery | 44 Ah |
| Alternator | 70 A |
Brakes
| Disc thickness, front, min. | 17.0 mm |
| Drum diameter, rear, max. | 201.0 mm |
| Disc thickness, front, min. | 9.7 (17.0) mm |
Steering and wheel alignment
| Toe-out, front | -15' ± 10' ° |
| Camber, front | -1°05' ± 45' ° |
| Castor, front | 2°15' ± 1° Estate 1°30' ± 1° ° |
| Toe-in, rear | 10' + 30' -20' ° |
| Camber, rear | -1°40' ± 30' ° |
| Toe-out, front | 05' - 25' ° |
| Camber, front | -1°25' - 05' ° |
| Castor, front | 1° - 3° ° |
| Toe-in, rear | -10' - 40' 4x4 -02' - 15' ° |
| Camber, rear | -1°40' ± 30' 4x4 -2° ± 40' ° |
Wheels and tyres
| Tyre size | 175/65R14 |
| Optional | 185/60R14 |
| Front tyre pressure | 2.1 bar |
| Rear tyre pressure | 1.8 bar |
| Tyre size | 195/60R14 |
| Front tyre pressure | 2.2 bar |
| Rear tyre pressure | 2.0 bar |
Capacities
| Engine sump, incl. filter | 4.0 l |
| Gearbox refill | 1.9 l |
| Cooling system | 7.2 l |
| Air-conditioner refrigerant | 700 (1993-1994) 900 (1994-1996) g |
| Air-conditioner compressor oil | 295 ml |
| Manual transmission | F18 |
| Gearbox refill | 1.9 (0mm) l |
| Gearbox refill | 3.0 - 3.5 l |
| Air-conditioner refrigerant | 750 (1993-1994) 1000 (1994-1995) g |
Torque settings
| Cylinder head bolts — Stage 1 | 25 Nm |
| Cylinder head bolts — Stage 2 | 60° ° |
| Cylinder head bolts — Stage 3 | 60° ° |
| Cylinder head bolts — Stage 4 | 60° ° |
| Cylinder head bolts — Stage 5 | T=80°C |
| Cylinder head bolts — Stage 6 | 30° - 45° ° |
| Cylinder head bolts — Stage 1 | 100 Nm |
| Cylinder head bolts — Stage 2 | 20 Nm |
| Cylinder head bolts — Stage 3 | 80° ° |
| Rear hub | 50 Nm + 30° / 45° Nm |
| Wheel nuts | 110 Nm |
| Spark plugs | 25 Nm |
| Cylinder head bolts — Stage 4 | 30° ° |
| Cylinder head bolts — Stage 6 | 30° ° |
| Rear hub | 25 Nm (<-1993½) Nm |
Workshop procedures for this engine
Step-by-step procedures from the workshop database.
Got a C18NZ problem? Ask for free.
Describe the symptoms — TorqFix replies with a diagnosis cited from verified workshop data.
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.
Seen a figure that does not match your manual? Write to us — we correct it and note when. support@torqfix.com
The story behind TorqFix →Workshop data on this page last updated 22 Aug 2026.