1. Verify Fuel Delivery:
* Fuel Pump: Listen carefully near the fuel tank for the whirring sound of the fuel pump when you turn the ignition key to the "on" position (before cranking). If you don't hear it, the fuel pump might be faulty or not getting power. You can also check the fuel pump relay.
* Fuel Filter: A clogged fuel filter can restrict fuel flow. It's a relatively cheap and easy part to replace.
* Fuel Pressure: This requires a fuel pressure gauge to check if the fuel pressure is adequate at the fuel rail. This is a more advanced check.
* Fuel Injectors: Less likely, but faulty injectors could prevent fuel from reaching the combustion chamber. This usually requires specialized tools and testing equipment.
2. Ignition System:
* Spark: Check for spark at the spark plugs. A simple way to do this is to remove a spark plug wire, hold the end of the wire about 1/4 inch from a good ground (like the engine block), and crank the engine. You should see a strong spark. If not, there's an issue in the ignition system.
* Ignition Coil: A faulty ignition coil can prevent spark.
* Distributor (if applicable): The distributor (if your model uses one) might have issues with the rotor, cap, or points. These components should be inspected and potentially replaced. A failing distributor can produce weak or intermittent spark.
* Ignition Switch: A faulty ignition switch may not be providing power to the necessary components.
* Cranking Speed: Is the engine cranking slowly or rapidly? Slow cranking could indicate a weak battery or a problem with the starting circuit.
3. Other Possibilities:
* Computer/ECU (Electronic Control Unit): While less common in a 1984 model, problems with the car's computer could disrupt fuel delivery or ignition. This would require specialized diagnostic tools.
* Sensor Issues: Various sensors (e.g., crankshaft position sensor, camshaft position sensor) can prevent the engine from starting. This is unlikely to be the problem unless you have other drivability issues.
* Security System (if equipped): An aftermarket or factory security system might be preventing the car from starting.
Troubleshooting Steps:
1. Start with the simplest and cheapest checks: Fuel pump, fuel filter, and checking for spark are good places to begin.
2. Use a multimeter: A multimeter is an invaluable tool for checking voltage, continuity, and resistance in various parts of the electrical system.
3. Consult a Volvo 240 repair manual: A repair manual specific to your year and model will provide detailed diagrams and troubleshooting guides.
4. Seek professional help: If you are not comfortable working on your car's electrical system, it's best to take it to a qualified mechanic familiar with older Volvos.
Remember safety first! Disconnect the negative battery terminal before working on any electrical components. Be aware of moving parts when cranking the engine.
