CASE 002
Engine Cranks But Will Not Start
intermediate
20 min
Petrol
Vehicle
- ModelTraining Hatch 1.6
- Engine1.6 16V
- Mileage132,000 km
Customer complaint
The engine turns over at normal speed but does not fire. The customer ran out of fuel last week.
History
Fuel was added after the car ran dry. It started once, then died and has not started since.
Fault codes
P0335 Crankshaft position sensor A circuitP0087 Fuel rail pressure too low
Live data
- Engine speed while cranking0 rpm
- Fuel rail pressure while crankingLow
Measurements
- Battery voltage while cranking11.4 V (acceptable)
- Fuel pressure at rail, key onLow
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Diagnostic case
Next step — Reasoning.
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Confirmed cause
No crankshaft signal — the engine speed PID stays at zero while cranking, so the ECU has no synchronisation and inhibits spark and injection.
Reasoning
A cranking engine with 0 rpm reported by the ECU is a classic no-synchronisation signature. Before assuming the sensor, check its supply, ground and wiring, and confirm the air gap and reluctor. Never replace a sensor on a code alone.
Recommended repair
- Test the crankshaft sensor reference, ground and signal.
- Inspect the wiring and connector for damage or contamination.
- Replace the sensor only if the tests confirm it, then verify synchronisation and start.
Related tools
Related OBD codes
All values shown are training examples. Real thresholds depend on the manufacturer, engine, temperature and system — always confirm with the vehicle service documentation.