1. The Basics (The "Easy" Checks):
* Battery: This is the MOST common cause. Check the battery voltage with a voltmeter. It should read around 12.6V when the engine is off. If it's low, charge it or replace it. Also, check the battery terminals for corrosion and clean them if necessary.
* Starter: Listen carefully when you turn the key. Do you hear a *click*, a *whirr*, or nothing at all?
* Click: This usually indicates a weak battery, a bad connection, or a failing starter solenoid.
* Whirr: The starter is engaging, but the engine isn't turning over. This could be a seized engine (rare but possible), a broken timing belt (more likely on higher mileage Rangers), or something obstructing the engine's rotation.
* Nothing: Could be a bad starter, a bad ignition switch, or a blown fuse/relay.
* Fuel: Can you smell fuel? Is the fuel gauge reading empty?
* Empty Gauge: Obviously, you need to add fuel.
* Fuel pump: Listen carefully near the fuel tank while someone turns the ignition key to the "on" position (don't crank). You should hear a brief hum from the fuel pump. If not, the pump might be faulty, the fuel pump relay might be bad, or there might be a problem with the fuel pump circuit.
2. If the Basics Check Out:
If the battery is good, the starter cranks, and you have fuel, move on to:
* Ignition System:
* Spark Plugs: Remove a spark plug, ground it to the engine block, and have someone crank the engine. You should see a strong, blue spark. If not, there's an issue in your ignition system. Check the spark plug wires for cracks or damage.
* Ignition Coil: A faulty coil can prevent spark. Testing requires a multimeter or a spark tester.
* Camshaft Position Sensor (CMP) and Crankshaft Position Sensor (CKP): These sensors are crucial for the engine to know when to fire the spark plugs. A faulty sensor will prevent the engine from starting. These often need professional diagnosis with a scan tool to pinpoint which sensor is failing.
* Distributor (if applicable): If your Ranger has a distributor, check the cap and rotor for wear and tear. Also, check the ignition module.
* Ignition Switch: A faulty ignition switch won't send power to the necessary components.
3. Beyond the Basics:
* Fuel Delivery: If you have spark, but still no start, investigate further issues with fuel delivery. A clogged fuel filter, a faulty fuel pressure regulator, or a problem with the fuel injectors are possibilities. A fuel pressure gauge can help diagnose this.
* Computer/ECU: A failing Engine Control Unit (ECU) can cause a no-start condition. This often requires diagnostic tools and professional help.
* Security System: If your truck has an aftermarket or factory alarm system, it might be preventing the engine from starting.
Important Considerations:
* Scan Tool: A scan tool (OBD-II reader) is invaluable for getting diagnostic trouble codes (DTCs). These codes can pinpoint the likely cause of the problem.
* Repair Manual: A repair manual specific to your 2001 Ford Ranger will provide wiring diagrams, component locations, and troubleshooting procedures.
* Professional Help: If you're not comfortable working on your vehicle's electrical system, it's best to seek professional help from a qualified mechanic. Incorrect diagnosis and repairs can lead to further damage.
Remember safety first! Disconnect the negative battery terminal before working on any electrical components. This prevents accidental shorts and shocks. Systematic troubleshooting is key to finding the cause of your no-start issue.
