* Timing: Even with spark, the timing could be significantly off. The spark might be occurring too early or too late in the engine's cycle, preventing combustion. Check the timing belt or chain for correct alignment and tension. A slightly off timing mark can make a car crank but not fire.
* Crankshaft Position Sensor (CKP): This sensor tells the computer the position of the crankshaft. A faulty CKP sensor will prevent the computer from delivering the spark at the correct time, even if the timing is mechanically correct.
* Cam Position Sensor (CMP): Similar to the CKP sensor, a faulty CMP sensor will prevent proper timing of the spark and fuel injection.
* Fuel Pressure Regulator: While you say it's getting fuel, the fuel pressure might be incorrect. A faulty fuel pressure regulator could allow too much or too little fuel into the cylinders. Test the fuel pressure to confirm it's within specifications.
* Fuel Injectors: Even with fuel reaching the engine, the injectors might be clogged, delivering insufficient fuel or no fuel at all to one or more cylinders. A fuel injector test is needed.
* Ignition Control Module (ICM): This module controls the ignition system. A faulty ICM can prevent spark, despite having a good coil and other components. While you mention spark, a weak spark from a failing ICM might not be sufficient for reliable combustion.
* Computer (PCM): The Powertrain Control Module (PCM) manages many aspects of the engine's operation. A faulty PCM can cause a wide range of problems, including preventing the engine from starting, even if all the other components are functioning correctly. This is a more difficult issue to diagnose.
* Engine Coolant Temperature (ECT) Sensor: A faulty ECT sensor can cause the computer to deliver incorrect fuel and spark signals, leading to starting problems.
* Mass Airflow Sensor (MAF): A faulty MAF sensor can lead to a lean fuel mixture, preventing the engine from starting.
Troubleshooting Steps:
1. Verify Fuel Pressure: Use a fuel pressure gauge to check fuel pressure. This is a crucial step.
2. Check for Spark Quality: While you have spark, is it strong and consistent across all cylinders? A weak spark might not be sufficient.
3. Inspect Timing Belt/Chain: Visually inspect for damage or misalignment.
4. Check the CKP and CMP Sensors: Use a multimeter or scanner to test these sensors for proper operation.
5. Test Fuel Injectors: Check for proper injector operation. This often requires specialized tools or a scan tool.
6. Inspect the ICM: Visual inspection for cracks or damage.
If you're not comfortable performing these checks yourself, take your Probe to a qualified mechanic. They have the tools and experience to diagnose the problem accurately and efficiently. A scan tool can provide valuable diagnostic trouble codes (DTCs) that will pinpoint the issue more quickly.
