1. Fuel System Issues:
- Fuel Pump: A weak or failing fuel pump may not be able to deliver enough fuel to the engine at higher RPMs, resulting in a loss of power and sputtering.
- Fuel Pressure: Low fuel pressure can cause the engine to run lean and result in hesitation or bogging at wide-open throttle. Check the fuel pressure to ensure it meets the specified range.
- Fuel Filter: A clogged fuel filter can restrict fuel flow and cause similar symptoms. Replace the fuel filter if it's dirty or clogged.
- Fuel Injectors: Dirty or malfunctioning fuel injectors can cause inconsistent fuel delivery, leading to bogging and sputtering. Cleaning or replacing the fuel injectors may resolve the issue.
2. Ignition System Problems:
- Spark Plugs: Worn-out or fouled spark plugs can cause misfires, resulting in a loss of power and sputtering. Inspect the spark plugs and replace them if necessary.
- Spark Plug Wires: Damaged or faulty spark plug wires can lead to inconsistent sparking and misfires, causing the engine to bog at higher RPMs. Check the spark plug wires and replace any that are cracked, damaged, or have loose connections.
- Distributor Cap and Rotor: A faulty distributor cap or rotor can disrupt the ignition timing and cause misfires. Inspect the distributor cap and rotor for cracks or damage and replace them if needed.
3. Air/Fuel Mixture Issues:
- Oxygen Sensor: A faulty oxygen sensor can provide incorrect feedback to the engine's computer, resulting in an incorrect fuel mixture. Check the oxygen sensor and replace it if it's malfunctioning.
- Mass Air Flow (MAF) Sensor: A dirty or faulty MAF sensor can provide incorrect information about the incoming air volume, affecting the fuel mixture. Clean the MAF sensor or replace it if necessary.
- Throttle Position Sensor (TPS): A malfunctioning TPS can provide incorrect information about the throttle position, causing the engine to run rich or lean at different throttle openings. Check the TPS and adjust or replace it if needed.
4. Vacuum Leaks:
- Hoses and Gaskets: Vacuum leaks can cause the engine to run lean, leading to bogging and sputtering. Inspect all vacuum hoses and gaskets for cracks, tears, or loose connections, and replace any that are damaged.
5. Timing Issues:
- Ignition Timing: Incorrect ignition timing can cause the engine to run poorly at higher RPMs. Verify the ignition timing and adjust it according to the manufacturer's specifications.
By systematically addressing these potential issues, you can narrow down and rectify the cause of the bogging and sputtering at wide-open throttle in your Chevy 350 engine. If the problem persists or you're unsure about performing these checks and adjustments, it's advisable to consult a qualified mechanic or automotive technician for further diagnosis and repair.
