Possible Causes:
* Fuel Delivery Issues (Beyond Just Having Fuel):
* Fuel Pump: Even if you have fuel in the tank, the pump might not be delivering it properly. Check fuel pressure at the rail.
* Fuel Filter: A clogged fuel filter can restrict fuel flow.
* Fuel Injectors: They could be clogged or malfunctioning.
* Ignition System Issues:
* Spark Plugs: Worn or fouled plugs can prevent spark.
* Spark Plug Wires: Damaged or cracked wires can hinder spark delivery.
* Distributor (if equipped): Check the rotor and cap for wear or cracks.
* Engine Sensors:
* Camshaft Position Sensor: If it's faulty, the engine won't know when to fire the spark plugs.
* Oxygen Sensor: While it doesn't directly affect starting, a faulty O2 sensor can cause the computer to send incorrect signals that could inhibit starting.
* Other Possibilities:
* Timing Belt/Chain: A slipped or broken timing belt/chain will cause major engine damage, but could also lead to no-start issues.
* Starter Issues: A weak starter can crank but not start.
Troubleshooting Steps:
1. Verify Fuel Delivery:
* Fuel Pressure: Use a fuel pressure gauge to check pressure at the fuel rail. Should be within manufacturer's specs.
* Fuel Pump Relay: If you hear a clicking noise when you turn the key, the fuel pump relay might be faulty.
* Fuel Filter: Inspect the filter for clogging.
2. Verify Spark:
* Spark Plugs: Check for proper spark at the plugs.
* Spark Plug Wires: Inspect for damage or cracks.
* Distributor (if equipped): Make sure the rotor and cap are in good condition.
3. Check Engine Sensors:
* Camshaft Position Sensor: This sensor is critical for timing.
* Oxygen Sensor: While less likely, a faulty sensor can prevent starting in some cases.
4. Inspect Other Components:
* Timing Belt/Chain: If you suspect a timing issue, inspect the belt/chain.
* Starter: Listen for a strong cranking sound. If it's weak, the starter may need replacement.
5. Use a Diagnostic Tool:
* An OBD-II scanner can help you read any trouble codes stored in the engine control unit (ECU). This can point you in the right direction.
Important Notes:
* Safety First: Disconnect the battery before working on the electrical system.
* Consult Repair Manual: Refer to your car's repair manual for specific diagnostic procedures and component specifications.
* Professional Help: If you're unsure, don't hesitate to take it to a trusted mechanic.
Let me know if you have any questions or would like to go through the troubleshooting steps in more detail!
