Possible Culprits:
1. Spark:
* Spark Plugs: Worn or fouled spark plugs can prevent a spark, hindering combustion. Inspect them for wear, discoloration, or gaps that are out of spec.
* Spark Plug Wires: Cracks, breaks, or corrosion in the wires can disrupt the electrical signal to the plugs. Check them for damage.
* Ignition Coil: A faulty coil won't deliver the necessary high voltage to the spark plugs. Test the coil for resistance and spark output.
* Distributor (if equipped): If your Integra has a distributor, inspect the cap and rotor for wear, cracks, or corrosion. Also, ensure the distributor's timing is correct.
2. Fuel Delivery:
* Fuel Filter: A clogged filter restricts fuel flow to the engine. Replace the fuel filter if it's old or suspect.
* Fuel Injectors: Clogged or faulty injectors may not deliver enough fuel to the cylinders. Inspect the injectors for proper operation.
* Fuel Pressure Regulator: This component regulates fuel pressure. A faulty regulator can cause inconsistent fuel pressure, leading to starting problems.
3. Engine Sensors:
* Crank Sensor: This sensor signals the ECU when the crankshaft is rotating. A faulty crank sensor won't allow the ECU to initiate the ignition sequence.
* Cam Sensor (if equipped): Similar to the crank sensor, a faulty cam sensor can disrupt the ignition timing.
* Oxygen Sensor: While not directly related to starting, a faulty oxygen sensor can confuse the ECU, leading to a lean fuel mixture and starting issues.
4. ECU (Engine Control Unit):
* ECU Failure: Although rare, the ECU itself can fail. This would require diagnostic tools and potentially replacement.
5. Other Considerations:
* Immobilizer (if equipped): Some Integras have an immobilizer system that prevents the engine from starting if it doesn't recognize the correct key.
* Starter Issues: While you mentioned cranking, a weak starter can still struggle to turn the engine over fast enough for combustion.
* Air Intake/Fuel Lines: Look for any leaks or obstructions in the air intake or fuel lines.
Troubleshooting Steps:
1. Check for Spark:
* Remove a spark plug wire, ground it to a metal part of the engine, and crank the engine. Look for a spark.
* Test the ignition coil with a multimeter or a spark tester.
2. Check Fuel Pressure:
* Connect a fuel pressure gauge to the fuel rail and measure the pressure. Compare it to the manufacturer's specifications.
3. Inspect Sensors:
* Visually inspect the crank and cam sensors (if equipped) for damage.
* Use a scan tool to check for any related sensor codes.
4. Use a Code Reader:
* A code reader can help pinpoint any fault codes related to the engine, helping you narrow down the problem.
Important Notes:
* If you're not comfortable working on your car, it's best to take it to a qualified mechanic for diagnosis and repair.
* Be careful when working with electrical components. Disconnect the battery before working on any wiring or sensors.
Let me know if you'd like more specific troubleshooting advice based on the symptoms you're seeing. The more information you provide, the more I can help!
