Most Likely:
* Injector Problem: The most probable cause is a faulty injector on the front driver's side. A bad injector won't spray fuel, leading to a misfire and the engine missing. The tapping noise could be the injector clicking erratically or a related mechanical issue. Testing the injector's resistance and spray pattern is crucial.
* Low Fuel Pressure: While you have spark, insufficient fuel pressure could prevent the injector from delivering enough fuel for combustion, resulting in a misfire. A fuel pressure gauge test is needed to confirm this.
Less Likely, but Possible:
* Worn or Damaged Valve: A worn or damaged intake valve on that cylinder could prevent proper sealing, leading to a loss of compression and a misfire. The tapping noise *might* be related to this, but it's less likely to be the primary cause given the fact that only that one cylinder is failing. A compression test would be needed.
* Clogged Fuel Injector: A partially clogged injector might still provide some fuel, but not enough for proper combustion. Again, the tapping could be related to this, but a full cleaning or replacement is usually the solution for this scenario.
* Wiring Issue (though less likely given you have spark): A very rare possibility is a damaged wire to the injector itself that prevents proper operation despite having spark.
* Faulty Crankshaft Position Sensor (CKP): While less probable given that only one cylinder is affected, a failing CKP sensor can cause intermittent misfires. But usually, a bad CKP causes much more widespread issues than one cylinder.
Troubleshooting Steps:
1. Visual Inspection: Carefully inspect the injector wiring harness on the front driver's side for any obvious damage, loose connections, or corrosion.
2. Fuel Pressure Test: Use a fuel pressure gauge to check fuel pressure. This is vital to rule out low pressure as a cause. Your Corvette's service manual will specify the correct pressure.
3. Injector Test: Test the injector's resistance (using a multimeter) and spray pattern (using a fuel injector tester). This confirms whether it's delivering fuel properly.
4. Compression Test: Perform a compression test on all cylinders. A significantly lower compression reading on the front driver's side cylinder suggests a valve problem or a blown head gasket.
5. Check for Vacuum Leaks: Significant vacuum leaks can affect fuel delivery. Inspect all vacuum lines and connections.
Important Note: Without proper diagnostic tools and experience working on vehicles, attempting repairs could worsen the problem. It's best to consult a qualified mechanic experienced with Corvettes. They will have the proper tools and knowledge to diagnose and repair the issue efficiently and safely.
