* Fuel Pump: This is the most common cause. A failing fuel pump may not be supplying enough fuel to the engine, or it might be completely failing. You'll need to have the fuel pressure tested to confirm.
* Fuel Filter: A clogged fuel filter restricts fuel flow to the engine. It's a relatively inexpensive part to replace, so it's worth checking.
* Crankshaft Position Sensor (CKP): This sensor tells the engine's computer the position of the crankshaft. A faulty CKP sensor can prevent the engine from getting the correct fuel/air mixture at the right time, resulting in a no-start condition.
* Camshaft Position Sensor (CMP): Similar to the CKP sensor, a faulty CMP sensor can disrupt the timing of fuel injection.
* Fuel Injectors: Clogged or faulty fuel injectors might not be spraying fuel properly. A fuel injector cleaning or replacement might be needed.
* PCM (Powertrain Control Module): In rare cases, a problem with the PCM (the engine's computer) can prevent it from sending the signals needed for proper fuel delivery. This is less likely but possible.
* Fuel Pressure Regulator: A faulty fuel pressure regulator can cause incorrect fuel pressure in the system.
Important Considerations & Safety:
* Don't keep using starter fluid: It's highly flammable and dangerous. Using it repeatedly can damage your engine. It is only a diagnostic tool.
* Professional Diagnosis: Your best course of action is to take your car to a qualified mechanic for diagnosis. They have the tools and expertise to properly test the fuel system and identify the specific problem. Relying on guesswork can lead to unnecessary repairs or further damage.
* Fire Hazard: Be extremely cautious when using starter fluid. Ensure the area is well-ventilated and keep away from open flames.
The fact that it starts *only* with starter fluid strongly points to a fuel delivery issue, but a proper diagnosis is crucial to avoid expensive guesswork. Getting it checked by a mechanic is the safest and most efficient way to solve the problem.
