APG engine — Seat 1.8 (1.8L)
1.8L · 125 hp
Engine overview
Vehicles with this engine
Factory specifications
Values from the manufacturer documentation for this engine.
Engine (general)
| Engine code | APG |
| Capacity | 1781 cc |
| Idle speed | 660 - 960 rpm |
| Idle speed | 800 - 860 rpm |
| Normal | 10.0 - 13.0 bar |
| Minimum | 7.0 bar |
| Differential limit between cylinders | 3.0 bar |
| Oil pressure | 3.5 - 4.5 / 2000 bar/rpm |
| Oil pressure | 1.3 / 860 bar/rpm |
Engine (petrol)
| Fuel system (make and type) | Bosch Motronic |
| Number of cylinders | 4 |
| Firing order | 1 - 4 - 3 - 2 |
| Spark plugs (make and type) | NGK BKUR6ET-10 |
| Spark plug gap | 1.0 mm |
| Injection pressure/system pressure | 4.0 bar |
| CO exhaust gas | < 0.5 % |
| CO at fast-idle speed | < 0.3 % |
| Fast-idle speed | 2500 - 2800 rpm |
| Lambda | 0.97 - 1.03 |
| Lambda change (Delta Lambda) | 0.03 |
| Oil temperature during test | 80 °C |
| Closed-loop test at: | 700 - 960 rpm |
| Closed-loop test at: | 560 - 960 rpm |
| Conditioning catalytic converter | 2 / 2500 min/rpm |
Cooling system
| Cap pressure | 1.4 - 1.6 bar |
| Thermostat opens at | 87 °C |
| Stage 1 | 92 - 97 °C |
| Stage 2 | 99 - 105 °C |
Capacities
| Engine sump, incl. filter | 4.5 l |
| Manual transmission | 02J |
| Gearbox refill | 1.9 l |
| Automatic transmission | 01M |
| Gearbox refill | 3.0 l |
| Differential | 0.75 l |
| Air-conditioner refrigerant | 750 - 800 g |
| Air-conditioner compressor oil | 120 - 150 ml |
Torque settings
| Cylinder head bolts — Stage 1 | 40 Nm |
| Cylinder head bolts — Stage 2 | 90 ° |
| Cylinder head bolts — Stage 3 | 90 ° |
| Spark plugs | 30 Nm |
| Main bearing cap | 65 Nm + 90° Nm |
| Big-end bearing cap | 30 Nm + 90° Nm |
| Oil plug | 30 Nm |
| Oxygen sensor | 55 Nm |
| Flywheel | 60 Nm + 90° Nm |
| Knock sensor | 20 Nm |
| Automatic transmission drain plug | 120 Nm |
Emissions
| Emission code | 70/220*1996/69 |
| Emission standard | Euro 2 (09/1997 ->) |
| CO2 average | 199 - 202 g/km |
| CO | 0.656 g/km |
| HC NOx | 0.140 g/km |
| Emission code | 70/220*1999/102A |
| Emission standard | Euro 3 (07/2000 ->) |
| CO2 average | 187 - 190 g/km |
| CO | 0.874 g/km |
| HC | 0.078 g/km |
| NOx | 0.036 g/km |
| CO2 average | 214 - 221 g/km |
| CO | 0.665 g/km |
| HC NOx | 0.181 g/km |
| CO2 average | 209 - 211 g/km |
| CO | 1.850 g/km |
| HC | 0.164 g/km |
| NOx | 0.110 g/km |
| Emission standard | Euro 2 (01/1999 ->) |
Engine codes in the same family
The same code prefix usually means the same block with a different output, fuel or model year. Procedures are often shared — check the code on the engine plate.
Workshop procedures for this engine
Step-by-step procedures from the workshop database.
- Removing and installing fuel tank with attached components
- Removing and installing suction-jet pump – Audi Q3
- Removing and installing fuel delivery unit – Audi Q7
- Adjusting accelerator position sender G79 - right-hand drive vehicles without accelerator pedal module
- Draining fuel tank – Audi Q5
- Removing and installing fuel gauge senderG – Audi A8 D4
- Checking fuel pump (electrical test)
- Replacing Motronic control unit -J220
- Checking fuel gauge senderG – Audi Q7
- Checking fuel pump delivery rate – Audi A8 D3
- Removing and installing parts of exhaust system
- Function of camshaft timing control
- Testing secondary air pump relay -J299 and activation
- Adaption of throttle valve control part
- Checking Hall sender -G40
- Removing and installing throttle cable – Audi A3
- Performing kick-down adaption - vehicles with automatic gearbox
- Checking system pressure, fuel pressure regulator and holding pressure
- Checking engine speed sender -G28
- Checking accelerator pedal position sender -G79 and -G185
- Electrical check of exhaust gas recirculation valve -N18 and potentiometer for exhaust gas recirculation -G212
- Checking activated charcoal filter solenoid valve 1 -N80
- Checking secondary air inlet valve -N112
- Checking throttle valve drive angle senders 1 and 2 -G187 and -G188
- Check brake light switch -F and brake pedal switch -F47
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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.