1. Fuel System Issues
* No fuel delivery:
* Empty tank: Check your fuel gauge, but even if it reads full, you might have a blocked fuel line or a faulty fuel pump.
* Fuel pump failure: Listen for the fuel pump to hum when you turn the key to the "on" position. If you don't hear it, the pump may have failed.
* Clogged fuel filter: A dirty fuel filter can restrict fuel flow.
* Fuel line blockage: Check for any kinks or debris in the fuel lines.
* Incorrect fuel-air mixture:
* Faulty fuel injectors: Injectors can become clogged or fail, preventing fuel from reaching the cylinders.
* Air leaks in the intake manifold: Cracks or loose connections in the intake manifold can draw in unmetered air, causing a lean mixture.
* Faulty fuel pressure regulator: A faulty fuel pressure regulator can result in either too much or too little fuel pressure.
2. Ignition System Problems
* Spark plugs: Check for spark plugs that are fouled, damaged, or have a worn electrode.
* Spark plug wires: Inspect wires for cracks, fraying, or loose connections.
* Ignition coil: Test the coil for proper voltage output.
* Distributor cap and rotor: Look for cracks, corrosion, or worn contacts in the distributor cap and rotor.
* Ignition control module (ICM): This part controls the spark timing. If it's faulty, it can prevent ignition.
3. Compression Issues
* Low compression: This can be caused by:
* Worn piston rings: Rings that are worn or damaged can allow compression to escape.
* Damaged valves: Bent or burned valves can also lead to low compression.
* Head gasket failure: A blown head gasket can allow coolant to leak into the cylinders, reducing compression.
4. Other Possibilities
* Timing belt/chain problems: If the timing belt or chain is broken or off, the engine will not fire.
* Faulty crankshaft position sensor: This sensor tells the computer the position of the crankshaft, and a faulty sensor can prevent ignition.
* Dead battery: While the engine may turn over, a weak or dead battery may not provide enough power to start the engine.
Troubleshooting Tips:
* Start with the basics: Check the fuel level, make sure the battery is charged, and inspect the spark plugs for signs of wear.
* Listen for clues: Pay attention to any unusual sounds coming from the engine.
* Use a code reader: A code reader can help identify any fault codes stored in the engine control module (ECM).
* Don't overlook the obvious: Sometimes the simplest things, like a loose wire or a blown fuse, can be the cause.
Important Note: If you're not comfortable working on your own car, it's best to take it to a qualified mechanic for diagnosis and repair.
