Simple Checks (Start Here):
* Battery: Is the battery charged? Test the voltage with a multimeter. A weak battery can prevent the ignition system from functioning properly. Check the battery terminals for corrosion and clean them if necessary.
* Ignition Switch: Is the ignition switch working correctly? Try turning the key to different positions and listen for clicks or unusual sounds. A faulty ignition switch can cut off power to the rest of the ignition system.
* Fuses: Check the fuses related to the ignition system. Your owner's manual will show you the fuse box location and diagram. A blown fuse will interrupt the circuit.
* Wiring: Visually inspect all wiring related to the ignition system for any obvious damage, such as frayed wires, loose connections, or corrosion. Pay close attention to the connections at the coil, distributor, and ignition switch. A broken wire is a common cause.
* Coil Wire: The wire running from the ignition coil to the distributor cap can be cracked or worn internally. This is often overlooked and is a major cause of no spark. Replace it if you suspect damage.
Intermediate Checks:
* Ignition Coil: Test the ignition coil using a multimeter to check for proper resistance. A faulty coil won't generate the high voltage needed for a spark.
* Distributor Cap and Rotor: Inspect the distributor cap and rotor for cracks, carbon tracking, or corrosion. These can prevent the spark from jumping across to the correct terminal. Replace them if damaged.
* Distributor: While less common, the distributor itself could be faulty (worn points in older distributors, internal failure in electronic systems). This usually requires more testing or a shop visit.
Advanced Checks (Likely requiring tools and/or experience):
* Ignition Module (if equipped): Some 1976 Chevys may have an ignition module (or control unit). This electronic component controls the timing and spark output of the coil. Testing this requires specialized equipment and knowledge.
* Pick-up coil (in distributor): The pick-up coil in the distributor is responsible for sending a signal to the ignition module (or points in older systems). If it is faulty, there will be no spark. Requires testing with a multimeter.
* Crankshaft Position Sensor (CPS) (if equipped): Newer distributors may have a CPS. This sensor tells the computer when to send a spark signal. A faulty CPS will result in no spark.
Troubleshooting Steps:
1. Start with the simplest checks (battery, fuses, wiring). These are the quickest and easiest things to rule out.
2. Use a multimeter to test the components that can be tested with it (coil, pick-up coil, etc).
3. Visually inspect all parts of the ignition system.
4. Replace suspect components one at a time after testing them, to isolate the problem.
If you are not comfortable working on your car's electrical system, it's best to take it to a qualified mechanic for diagnosis and repair. Incorrectly working on electrical systems can be dangerous. Remember safety first! Always disconnect the negative battery terminal before starting any electrical work on your vehicle.
