Spark plug wires: Check the spark plug wires to make sure they are in good condition and properly connected. Faulty spark plug wires can cause misfires, which can lead to vibration and reduced fuel efficiency.
Ignition coil: A faulty ignition coil can also cause misfires and lead to vibration and poor gas mileage. Check the ignition coil for cracks or other damage and replace it if necessary.
Oxygen sensors: The oxygen sensors monitor the exhaust gas and help the engine adjust the fuel mixture accordingly. Faulty oxygen sensors can cause the engine to run rich or lean, which can lead to vibration and reduced fuel efficiency. Check the oxygen sensors for damage and replace them if necessary.
Fuel injectors: The fuel injectors deliver fuel to the engine. Clogged or faulty fuel injectors can cause the engine to run rough and reduce fuel efficiency. Clean the fuel injectors or replace them if necessary.
Mass air flow sensor: The mass air flow sensor measures the amount of air entering the engine. A faulty mass air flow sensor can cause the engine to run rich or lean, which can lead to vibration and reduced fuel efficiency. Check the mass air flow sensor for damage and replace it if necessary.
Exhaust system: Check the exhaust system for leaks or damage. Exhaust leaks can cause vibration and reduced fuel efficiency. Inspect the exhaust system for holes or cracks and repair or replace any damaged components.
Transmission: A faulty transmission can also cause vibration and reduced fuel efficiency. Check the transmission fluid level and condition, and have the transmission inspected by a qualified mechanic if necessary.
By addressing these potential causes, you may be able to resolve the vibration under the seat and improve the gas mileage in your 2002 Corvette. If the problem persists, it is recommended to have the vehicle inspected by a professional mechanic to diagnose and repair the issue accurately.
