1. Fuel System:
* Empty Tank: The most obvious! Check your fuel gauge.
* Fuel Pump: The pump might be failing to deliver fuel. You might hear a whirring sound from the fuel pump when you turn the key to the "on" position (before cranking). If you don't hear it, the pump might be bad. A mechanic can test the fuel pressure.
* Fuel Filter: A clogged fuel filter restricts fuel flow. It's a relatively inexpensive part to replace.
* Fuel Injectors: These spray fuel into the cylinders. They can become clogged or fail. A mechanic can test the injectors.
* Fuel Pressure Regulator: This regulates the fuel pressure in the system. A faulty regulator can cause low fuel pressure.
2. Ignition System:
* Spark Plugs & Wires: Worn, fouled, or loose spark plugs and wires prevent a spark from reaching the cylinders. Inspect them for damage, corrosion, or gaps that are too wide or narrow.
* Ignition Coil: This provides the high voltage needed for the spark. A faulty coil won't produce sufficient voltage.
* Distributor (if applicable): Older cars like your Regal may have a distributor. Issues within the distributor, such as a bad cap or rotor, can prevent spark.
* Crankshaft Position Sensor (CKP): This sensor tells the computer the position of the crankshaft. A faulty sensor won't allow the ignition system to fire.
* Camshaft Position Sensor (CMP): Similar to the CKP sensor, but for the camshaft.
* Ignition Control Module (ICM): This module controls the ignition system.
3. Compression:
* Low Compression: This means the engine isn't compressing the air-fuel mixture properly. This could be due to worn piston rings, a blown head gasket, or valve problems. A compression test is necessary to diagnose this.
Troubleshooting Steps:
1. Check the obvious: Fuel level, spark plug wires (are they connected securely?), and listen for the fuel pump whirring.
2. Check for spark: Use a spark tester on a spark plug wire to see if you're getting spark. This requires removing a spark plug and grounding it. Be careful!
3. Listen for the fuel pump: Turn the key to the "on" position (but don't crank) and listen near the fuel tank for the whirring sound of the fuel pump. If it's not running, you've got a fuel pump problem.
4. Check fuel pressure: This usually requires a fuel pressure gauge. A mechanic can do this quickly.
Important Note: Without more information or diagnostic testing, it's impossible to pinpoint the exact cause. If you're not comfortable working on your car, it's best to take it to a qualified mechanic for diagnosis and repair. They have the tools and expertise to properly diagnose the problem.
