Simple Checks (Do these FIRST):
* Fuel:
* Empty tank? Sounds obvious, but worth checking.
* Fuel pump: Listen carefully near the fuel tank while someone turns the key to the "on" position (don't crank). You should hear a brief humming sound. If not, the fuel pump may be faulty.
* Fuel filter: A clogged fuel filter will restrict fuel flow.
* Fuel injectors: These spray fuel into the cylinders. A faulty injector (or several) will prevent combustion. Testing these usually requires specialized tools.
* Ignition:
* Ignition coil: This component provides the high voltage needed to fire the spark plugs. A faulty coil can cause misfires or no spark at all. This is a common issue on Rangers.
* Distributor (if applicable): Older Rangers might have a distributor; if so, ensure the rotor and cap are in good condition and properly seated. Cracks or corrosion can disrupt the spark signal.
* Ignition switch: A failing ignition switch won't send power to the necessary components.
* Crankshaft Position Sensor (CKP): This sensor tells the computer the engine's rotational position. A faulty CKP will prevent the engine from starting.
* Camshaft Position Sensor (CMP): Similar to the CKP, this sensor monitors the camshaft's position.
* Other:
* Battery: A weak or dead battery can prevent starting, even if the ignition system is fine. Test the battery voltage.
* Starter: If the engine doesn't even crank, the starter motor might be at fault.
* Security system: Some vehicles have immobilizers that prevent starting if the correct key isn't used.
More Complex Issues (Requires more specialized tools or knowledge):
* Computer/ECU Problems: A faulty engine control module (ECM) or other computer issues can cause a no-start condition. This requires diagnostic tools to check for error codes.
* Wiring Problems: Damaged or corroded wiring can interrupt the electrical signals needed for starting. A visual inspection of all wiring related to the ignition and fuel systems is recommended.
* Low Compression: If the engine's compression is low in one or more cylinders, it won't start. This requires a compression test.
Troubleshooting Steps:
1. Start with the simple checks (fuel, battery, obvious visual inspections). These are the easiest and cheapest to rule out.
2. Listen for the fuel pump.
3. Check for spark at the spark plugs using an inline spark tester (don't touch the plug while testing!).
4. Obtain a diagnostic code reader. This is crucial for identifying potential problems within the computer system. Auto parts stores often have code readers available for rent or use.
5. If you're not comfortable working on your own vehicle, take it to a qualified mechanic.
Remember safety first! Disconnect the negative battery terminal before working on any electrical components. If you're not comfortable working on cars, it's best to seek professional help to avoid further damage.
