1. Simple Checks (Start Here):
* Battery and Connections: A dead or weak battery, corroded terminals, or loose connections are the most frequent cause of no spark. Check the battery voltage with a multimeter. Clean the terminals thoroughly.
* Ignition Switch: A faulty ignition switch might not be sending power to the rest of the ignition system. This is less common but possible.
* Fuses and Relays: Check the fuses and relays related to the ignition system. Your owner's manual will show fuse box diagrams.
2. Ignition Components:
* Ignition Coil: This component steps up the voltage from the battery to create the high voltage needed for spark. A bad coil will result in no spark. You'll likely need a multimeter to test its resistance.
* Ignition Control Module (ICM): The ICM is the "brains" of the ignition system, controlling the firing order and timing. A faulty ICM can prevent spark. These are often difficult to test without specialized equipment.
* Distributor Cap and Rotor: These components distribute the high voltage to the spark plugs. Cracks, corrosion, or worn contacts in the cap and rotor will prevent or weaken the spark. Visually inspect them.
* Spark Plug Wires: Damaged, frayed, or cracked spark plug wires can interrupt the high-voltage signal to the spark plugs. Check for visual damage and use an inline spark tester to verify they're carrying spark.
* Spark Plugs: Worn or fouled spark plugs will prevent a strong spark, or no spark at all. Replace them as a preventative measure if they're old.
3. Less Common but Possible Causes:
* Crank Position Sensor (CKP): This sensor tells the ICM when to fire the spark. A faulty CKP will prevent the ignition from firing.
* Cam Position Sensor (CMP): Similar to the CKP, a faulty CMP can cause ignition problems.
* Pick-up Coil (within the distributor): This coil senses the position of the rotor and sends a signal to the ICM.
* Wiring Issues: Broken or corroded wires anywhere in the ignition system can disrupt the electrical flow.
Troubleshooting Steps:
1. Start with the simple checks: Battery, terminals, fuses, and relays.
2. Visually inspect: Distributor cap, rotor, and spark plug wires.
3. Use a multimeter: Test the battery voltage, and if you're comfortable, test the ignition coil and other components.
4. Use an inline spark tester: This will help determine if the coil is producing high voltage and if that voltage is getting to the spark plug wires.
5. Consider professional help: If you're not comfortable working on your car's electrical system, take it to a mechanic. Diagnosing ignition problems can be tricky.
Remember safety first! Disconnect the negative battery terminal before working on any electrical components. Always refer to your vehicle's repair manual for specific information and diagrams.
