1. Fuel System Problems:
* Empty or Low Fuel: The most obvious, but worth checking first.
* Fuel Pump Failure: The pump might be weak, failing to deliver enough fuel to the engine. Listen carefully near the fuel tank for the whirring sound of the pump when the key is turned to the "on" position (not cranking). If you don't hear it, or hear a weak whir, it's a suspect.
* Clogged Fuel Filter: A clogged filter restricts fuel flow.
* Fuel Injectors: Clogged or faulty injectors prevent fuel from reaching the cylinders.
* Fuel Pressure Regulator: A faulty regulator could be causing incorrect fuel pressure.
2. Ignition System Problems:
* Spark Plugs: Worn, fouled, or improperly gapped spark plugs prevent ignition.
* Spark Plug Wires: Damaged or loose wires interrupt the spark. Check for cracks or fraying.
* Distributor Cap and Rotor: These components distribute the spark to the spark plugs. Look for cracks, corrosion, or wear. A bad distributor cap can cause misfires or no spark at all.
* Ignition Coil: This component boosts the voltage to create the spark. A faulty coil will prevent sparking.
* Ignition Control Module (ICM): This module controls the ignition timing. A malfunctioning ICM can lead to a no-start condition. (Common failure point on older Chryslers)
* Crank Position Sensor (CKP): This sensor tells the computer the crankshaft's position, crucial for ignition timing. A faulty CKP will prevent the engine from starting.
* Cam Position Sensor (CMP): Similar to the CKP, but for the camshaft. Again, crucial for timing.
3. Other Potential Issues:
* Battery Terminals: Corroded or loose battery terminals can prevent sufficient current flow. Clean and tighten them.
* Security System: Some older cars had rudimentary security systems that could prevent starting if they malfunction.
* Engine Control Module (ECM)/PCM: The computer controlling the engine could be faulty. This is a more complex diagnosis and usually requires professional help.
* Neutral Safety Switch: Automatic transmissions have a switch that prevents starting unless the gear selector is in Park or Neutral.
* Starter Motor (unlikely given it cranks): While it cranks, a weak starter might not provide enough power for starting. It's less likely if the engine turns over strongly.
Troubleshooting Steps:
1. Check the basics: Fuel level, battery terminals, and the obvious visual inspections of the distributor cap and rotor and spark plug wires.
2. Listen for the fuel pump: Turn the key to the "on" position (not cranking) and listen near the fuel tank for the pump.
3. Check for spark: Carefully test the spark plugs using a spark tester (or even a spare plug wired to a wire and grounded to the engine block). Caution: High voltage!
4. Check fuel pressure: This requires a fuel pressure gauge and is a more advanced step.
If you're not comfortable working on cars yourself, take it to a mechanic. Giving them the information about what you've already checked will help them diagnose the problem more efficiently. Mentioning that it cranks but doesn't start is key information.
