* Cranking speed: Is the engine cranking *strongly* or slowly? A weak crank could mean a bad battery, starter motor, or alternator. A weak crank might not provide enough power to reliably ignite the fuel-air mixture.
* Spark: Even with fuel pressure, the engine won't start without spark. Check the following:
* Ignition coil: Could be faulty or have a bad connection.
* Spark plugs and wires: Check for wear, damage, or corrosion. A simple visual inspection might suffice, but testing with a spark tester is more reliable.
* Crankshaft Position Sensor (CKP) or Cam Position Sensor (CMP): These sensors tell the computer the engine's rotational position to time the spark. A faulty sensor prevents proper spark timing.
* Ignition control module (ICM): This is part of the ignition system and could be failing.
* Fuel injectors: Even with sufficient fuel pressure, the injectors might be clogged, electrically faulty, or not receiving the signal to open. This would require more advanced diagnostic testing.
* Computer (PCM): The Powertrain Control Module (PCM) controls many aspects of the engine, including fuel delivery and spark. A faulty PCM can prevent the engine from starting even if all other components are working. This is less likely, but possible.
* Security system: Some vehicles have security systems that prevent starting if the key isn't recognized properly or there's a fault in the system.
Troubleshooting Steps:
1. Check the battery and charging system: Make sure the battery has sufficient voltage and the alternator is charging properly.
2. Verify spark: Use a spark tester to check for spark at the spark plugs.
3. Inspect the fuel injectors: Listen for a clicking sound from the injectors when cranking. This is a rudimentary check, a proper test requires a scan tool.
4. Scan for diagnostic trouble codes (DTCs): Use an OBD-II scanner to check for any stored codes. These codes can point to the specific problem area.
5. Check the CKP and CMP sensors: These are more involved and might require a multimeter or oscilloscope to properly test.
Because you've already checked fuel pressure (and it seems to be okay), focus your efforts on spark and the engine's ability to crank strongly. A professional mechanic will have the tools and expertise to diagnose the problem more effectively, especially if you're not comfortable working on automotive systems.
