1. Battery and Electrical System:
* Battery Terminals: Corrosion on the battery terminals is a very common cause. Clean them with a wire brush and baking soda and water solution. Make sure the connections are tight.
* Battery Voltage: Use a multimeter to check the battery voltage. It should be around 12.6 volts when fully charged. A lower voltage indicates a weak or dead battery. A voltage below 10 volts likely won't start the car. Check the battery cables themselves for any breaks in the wire.
* Battery Cables: Inspect the cables for any damage, fraying, or loose connections. Wiggle them gently to ensure they are securely fastened.
* Alternator: If the battery is weak and you suspect a charging issue, have the alternator tested at an auto parts store. A failing alternator won't charge the battery while the engine is running.
* Starter Motor: This is a crucial part for starting. If you turn the key and hear absolutely nothing, a bad starter is possible. However, sometimes you hear a clicking sound which points towards a weak battery, bad cables, or a faulty solenoid.
2. Ignition System:
* Ignition Switch: A faulty ignition switch can prevent the car from starting. This is less common but possible. Try wiggling the key while attempting to start.
* Ignition Coil: This provides the spark for the engine. A failing coil often leads to misfires or no spark at all. This usually requires professional diagnostic tools to check.
* Distributor (if equipped): Older vehicles may have a distributor. Inspect the cap and rotor for cracks or wear. If there's visible damage, replace it. (The '95 Windstar might not have a distributor, it depends on the engine).
* Spark Plugs and Wires: Worn spark plugs and wires can prevent the engine from firing. Check for damage or corrosion.
3. Fuel System:
* Fuel Pump: A faulty fuel pump can prevent fuel from reaching the engine. You might hear a whining noise from the fuel pump when you turn the key to the "on" position (before cranking). If you don't hear anything, the pump might be bad.
* Fuel Filter: A clogged fuel filter restricts fuel flow. Replacing it is relatively inexpensive.
* Fuel Injectors: Faulty fuel injectors can prevent fuel from being sprayed into the engine. Diagnosing this usually requires a fuel pressure test or scan tool.
4. Other Possibilities:
* Security System: If equipped, a malfunctioning security system can prevent the engine from starting.
* Neutral Safety Switch (Automatic Transmission): Makes sure the transmission is in Park or Neutral before the engine will crank.
* Sensors: Various sensors (crankshaft position sensor, camshaft position sensor, etc.) are crucial for the engine's operation. A faulty sensor will prevent the engine from starting. This is typically diagnosed using an OBD-II code reader.
Troubleshooting Steps:
1. Start with the simplest checks: Battery terminals, battery voltage, and visual inspection of cables.
2. Listen carefully: Do you hear any clicking noises, whining noises, or nothing at all when you turn the key?
3. Check fuses and relays: Inspect fuses related to the ignition system and fuel pump.
4. If you're comfortable, try some basic tests yourself: Check the battery voltage, inspect spark plugs, etc. Otherwise, take it to a mechanic.
5. Consider an OBD-II scan: A code reader can diagnose problems related to sensors and other electronic components.
If you're not comfortable working on your car yourself, take it to a qualified mechanic. Providing more details about what happens when you try to start the car (e.g., clicking, cranking, nothing at all) will help narrow down the possibilities.
