1. Fuel Supply:
* Empty Tank: The most obvious—is the tank actually empty? Check the fuel gauge, but also consider it might be faulty.
* Fuel Pump: This is a common culprit. Listen carefully near the fuel tank (you might need to have someone turn the ignition key to "on" – don't crank – to hear it). You should hear a brief humming sound as the pump primes. If you hear nothing, the pump might be failed.
* Fuel Pump Relay: The fuel pump relay might be bad and preventing power from reaching the pump. You'll need to locate the relay (check your owner's manual or online forums for its location) and test it with a multimeter or swap it with a known good relay of the same amperage.
* Clogged Fuel Filter: A clogged fuel filter restricts fuel flow. This is relatively inexpensive and easy to replace. It's usually located near the fuel pump or engine.
* Fuel Lines: Check for cracks, kinks, or leaks in the fuel lines running from the tank to the engine. Look carefully, and even consider a pressure test (this requires special equipment).
2. Fuel Delivery:
* Fuel Injectors: These spray fuel into the cylinders. A clogged or faulty injector can prevent fuel from reaching the engine. Testing injectors requires specialized tools.
* Fuel Pressure Regulator: This regulates fuel pressure in the system. A malfunctioning regulator can cause low or erratic fuel pressure.
* Intake Manifold Leaks: A large vacuum leak can cause a lean fuel condition preventing proper combustion, even with fuel reaching the system.
3. Ignition System (Could mimic fuel issues):
While you stated no gas to the engine, a problem with the ignition system (distributor cap, rotor, ignition coil, spark plugs, wires) could prevent the engine from starting even if fuel is present. It's worth checking these, especially if you hear nothing when you try to start the car.
Troubleshooting Steps:
1. Start with the simplest: Check the fuel gauge and visually inspect the fuel lines for obvious damage.
2. Listen for the fuel pump: This is a quick and easy way to eliminate a potential major component.
3. Check the fuel filter: This is a relatively cheap and easy fix that often solves the problem.
4. Consult a repair manual: A shop manual specific to your 1989 Grand Marquis will provide diagrams and detailed troubleshooting steps. Online forums dedicated to Ford vehicles (like Ford-trucks.com or similar) are invaluable resources.
5. Consider professional help: If you're uncomfortable working on your car's fuel system, take it to a qualified mechanic. Working with fuel is dangerous; incorrect handling can lead to fire or explosion.
Remember safety first! Work in a well-ventilated area and avoid sparks or flames when dealing with fuel systems.
