Select a fuel type and symptom:
Petrol
Engine will not crank
| Check: | Further Information: |
| Discuss fault with customer | Module 13.1 |
| Battery | Module 1.2 and Module 13.3 |
| Battery connections | Module 1.2 |
| Volt drop earth and live connections from battery to starter motor |
All Module 2 |
| Terminal 50 supply | All Module 2 |
| Starter motor | All Module 2 |
| Engine seized / hydraulic locked | Module 13.9 |
Engine cranks slower then normal
| Check: | Further Information: |
| Discuss fault with customer | Module 13.1 |
| Battery | Module 1.2 and Module 13.3 |
| Battery connections | Module 1.2 |
| Volt drop earth and live connections from battery to starter motor |
All Module 2 |
| Starter motor / current draw | All Module 2 and waveform 14.4.13 |
Engine cranks faster then normal
Engine cranks but fails to start
| Check: | Further Information: |
| Discuss fault with customer | Module 13.1 |
| Ignition system for HT spark | Module 4.2 |
| Fuel pump inertia switch | Module 5.1 |
| Fuel system for fuel pressure/delivery (fuel in tank) | Module 5.3 and waveform 14.2.4 |
| Fuel injection system for injector pulse | Waveform 14.2.7 |
| Engine compression | Module 13.9 |
| Scan DTCs | Module 12.2 |
| Check for contaminated fuel | Module 5.3 |
Engine starts then cuts out immediately
| Check: | Further Information: |
| Discuss fault with customer | Module 13.1 |
| Restriction in inlet system / throttle body | Module 5.1 |
| Monitor ignition system for HT spark | Module 4.2 |
| Monitor fuel system for fuel pressure / delivery (fuel in tank) |
Module 5.3 and waveform 14.2.4 |
| Monitor fuel injection system for injector pulse | Waveform 14.2.7 |
| Review live data on scan tool | Module 12.8 |
| Wiggle test wiring looms | Module 1.1 |
Engine starts but will not rev
| Check: | Further Information: |
| Discuss fault with customer | Module 13.1 |
| Restrictions in inlet systems / throttle valve | Module 5.1 |
| Restrictions in exhaust system | Module 9.1 |
| EGR valve | Module 8.2.6 |
| Electronic throttle control system | Module 8.2.5 |
| Throttle position sensor | Module 8.1.7 |
| Coolant temperature sensor | Module 8.1.1 |
| Monitor fuel system for fuel pressure / delivery (fuel in tank) |
Module 5.3 and waveform 14.2.4 |
| Monitor fuel injection system for injector pulse expansion |
Waveform 14.2.7 |
| Scan DTCs | Module 12.2 |
| Review live data on scan tool | Module 12.8 |
| Monitor performance of Air Flow Meter | Module 8.1.8 |
Engine starts but lacks power
| Check: | Further Information: |
| Discuss fault with customer | Module 13.1 |
| Restrictions in inlet systems / throttle valve | Module 5.1 |
| Restrictions in exhaust system | Module 9.1 |
| EGR valve | Module 8.2.6 |
| Coolant temperature sensor | Module 8.1.1 |
| Electronic throttle control system | Module 8.2.5 |
| Monitor fuel system for fuel pressure / delivery (fuel in tank) |
Module 5.3 and waveform 14.2.4 |
| Monitor fuel injection system for injector pulse expansion |
Waveform 14.2.7 |
| Scan DTCs | Module 12.2 |
| Review live data on scan tool | Module 12.8 |
| Monitor performance of Air Flow Meter | Module 8.1.8 |
| If turbocharged: monitor boost pressure | Module 8.1.11 |
| If turbocharged: check condition of vacuum hoses to wastegate valve |
Module 8.4.5 |
| Contaminated fuel | Module 5.3 |
Engine starts but misfires
| Check: | Further Information: |
| Discuss fault with customer | Module 13.1 |
| Scan DTCs | Module 12.2 |
| EGR valve | Module 8.2.6 |
| Review live data on scan tool | Module 12.8 |
| Monitor ignition system | Module 4.3 |
| Monitor fuel injectors | Waveform 14.2.7 |
| Compression test | Module 13.9 |
| Cylinder head gasket | Module 13.9 |
| Check vacuum stability | Module 13.9 |
| Check emissions | Module 9.1 |
| Contaminated fuel | Module 5.3 |
Engine starts but backfires through inlet
| Check: | Further Information: |
| Discuss fault with customer | Module 13.1 |
| Check vacuum stability (sticky inlet valves) | Module 13.9 |
| Check emissions | Module 9.1 |
| Ignition timing | Module 4.1 |
Engine starts but backfires through exhaust
| Check: | Further Information: |
| Discuss fault with customer | Module 13.1 |
| Check emissions | Module 9.1 |
| Ignition timing | Module 4.1 |
Engine starts but CO reading too high
| Check: | Further Information: |
| Discuss fault with customer | Module 13.1 |
| Intake system for blockages / air filter condition | Module 5.1 |
| Operation of oxygen sensor | Module 8.1.12 |
| Scan DTCs | Module 12.2 |
| Review live data on scan tool: airflow meter, coolant temperature sensor |
Module 12.8 |
| Fuel pressure / fuel pressure regulator | Module 5.3 |
| Injectors preformance / flow rate | Module 8.2.2 |
| Catalytic convertor | Module 9.1 |
| Engine crankcase breather / EVAP system fault | Module 9.3 |
Engine starts but blue smoke
| Check: | Further Information: |
| Discuss fault with customer | Module 13.1 |
| Engine oil level | Module 13.9 |
| Engine crankshaft / breather system | Module 9.3 |
| Compression test | Module 13.9 |
| Contaminated fuel | Module 5.3 |
Engine starts but white smoke
Diesel
Engine will not crank
| Check: | Further Information: |
| Discuss fault with customer | Module 13.1 |
| Battery | Module 1.2 and Module 13.2 |
| Battery connections | Module 1.2 |
| Volt drop earth and live connections from battery to starter motor |
All Module 2 |
| Terminal 50 supply | All Module 2 |
| Starter motor | All Module 2 |
| Engine seized / hydraulic locked | Module 13.9 |
Engine cranks slower then normal
| Check: | Further Information: |
| Discuss fault with customer | Module 13.1 |
| Battery | Module 1.2 and Module 13.2 |
| Battery connections | Module 1.2 |
| Volt drop earth and live connections from battery to starter motor |
All Module 2 |
| Starter motor / current draw | All Module 2 and waveform 14.4.14 |
Engine cranks faster then normal
Engine cranks but fails to start
| Check: | Further Information: |
| Discuss fault with customer | Module 13.1 |
| Non-common rail see Chapter 6.2 | Chapter 6.2 |
| High pressure fuel pump drive belt | Module 6.5 |
| Throttle valve jammed shut | Module 8.4.5 |
| Air ingress into the fuel lines | Module 6.1 |
| Fuel system for fuel low pressure / delivery (fuel in tank) |
Module 8.2.3 |
| Fuel system for high / rail pressure | Module 8.3.5 |
| Fuel injection system for injector pulse | Waveform 14.5.7 |
| Cam / pump belt timing / condition | Module 6.5 |
| Engine compression | Module 13.9 |
| Scan DTCs | Module 12.2 |
| Glow plugs (indirect injection only) | Module 8.4.1 |
Engine starts then cuts out immediately
| Check: | Further Information: |
| Discuss fault with customer | Module 13.1 |
| Restriction in inlet system / throttle body | Module 6.5 |
| Restriction in exhaust system | Module 9.4 |
| Monitor high fuel pressure | Module 8.3.5 |
| Monitor low fuel pressure / delivery | Module 8.2.3 and waveform 14.2.4 |
| Monitor fuel injection system for injector pulse | Waveform 14.5.7 |
| Scan DTCs | Module 12.2 |
| Review live data on scan tool | Module 12.8 |
| Wiggle test wiring looms | Module 1.1 |
| Contaminated fuel | Module 6.8 |
Engine starts but will not rev
| Check: | Further Information: |
| Discuss fault with customer | Module 13.1 |
| Restrictions in inlet systems / throttle valve | Module 6.5 |
| Restrictions in exhaust system | Module 9.4 |
| EGR valve | Module 8.2.6 |
| Electronic throttle control system | Module 8.2.5 |
| Throttle position sensor | Module 8.1.7 |
| Monitor high fuel pressure | Module 8.3.5 |
| Monitor fuel injector for main pulse expansion | Waveform 14.5.7 |
| Fuel quantity control valve | Module 8.4.3 |
| Scan DTCs | Module 12.2 |
| Review live data on scan tool | Module 12.8 |
| Monitor performance of Air Flow Meter | Module 8.3.3 |
| Contaminated fuel | Module 6.8 |
Engine starts but lacks power
| Check: | Further Information: |
| Discuss fault with customer | Module 13.1 |
| Restrictions in inlet systems / throttle valve | Module 6.5 |
| Restrictions in exhaust system | Module 9.4 |
| EGR valve | Module 8.2.6 |
| Electronic throttle control system | Module 8.2.5 |
| Monitor fuel injection system for injector pulse expansion / phases |
Waveform 14.5.8 |
| Fuel quantity control valve | Module 8.4.3 |
| Scan DTCs | Module 12.2 |
| Review live data on scan tool | Module 12.8 |
| Monitor performance of Air Flow Meter | Module 8.3.3 |
| If turbocharged: monitor boost pressure | Module 8.3.2 |
| Contaminated fuel | Module 6.8 |
| Poor injector atomisation | Module 8.4.4 |
| Fuel filter water trap | Module 6.5 |
Engine starts but misfires
| Check: | Further Information: |
| Discuss fault with customer | Module 13.1 |
| Scan DTCs | Module 12.2 |
| Review live data on scan tool | Module 12.8 |
| Monitor high fuel pressure | Module 8.3.5 |
| Cylinder head gasket | Module 13.9 |
| Contaminated fuel | Module 5.3 |
| Fuel filter water trap | Module 6.5 |
| Test injectors | Module 8.4.4 |
Engine starts but black smoke
| Check: | Further Information: |
| Discuss fault with customer | Module 13.1 |
| Scan DTCs | Module 12.2 |
| Review live data on scan tool | Module 12.8 |
| Restrictions in inlet systems / throttle valve | Module 6.5 |
| Test injectors | Module 8.4.4 |
Engine starts but blue smoke
| Check: | Further Information: |
| Discuss fault with customer | Module 13.1 |
| Engine oil level | Module 13.9 |
| Engine crankshaft / breather system | Module 9.3 |
| Compression test | Module 13.9 |
| Worn turbocharger | Module 15.6 |
| Contaminated fuel | Module 6.8 |
Engine starts but white smoke
| Check: | Further Information: |
| Discuss fault with customer | Module 13.1 |
| Cylinder Headgasket | Module 13.9 |
| Water ingress into fuel | Module 6.1 |
| Poor injector atomisation | Module 8.4.4 |