Fuel System Issues (Most Likely):
* Fuel Pump: A weak or failing fuel pump can't deliver enough fuel to the engine under acceleration. This is a common cause of stalling, especially when demanding more power. Listen for a humming sound from the fuel pump (usually near the fuel tank) when the ignition is turned on. A weak hum or no hum suggests a problem.
* Fuel Filter: A clogged fuel filter restricts fuel flow, leading to similar symptoms as a failing fuel pump. It's a relatively inexpensive part to replace and should be checked regularly.
* Fuel Injectors: Clogged or faulty fuel injectors can prevent proper fuel delivery to the cylinders. This requires more specialized diagnostics to pinpoint which injector(s) are problematic.
* Fuel Pressure Regulator: This component regulates fuel pressure within the system. A faulty regulator can cause inconsistent fuel pressure, leading to stalling.
Ignition System Issues:
* Distributor Cap and Rotor: Wear and tear on these components can cause intermittent spark delivery, leading to misfires and stalling, particularly under load (acceleration). Inspect for cracks, corrosion, or worn contacts.
* Ignition Coil: A failing ignition coil won't produce sufficient spark energy to ignite the fuel-air mixture consistently.
* Spark Plugs and Wires: Worn spark plugs or damaged wires can also cause misfires and stalling. Check for gaps, corrosion, and cracks.
Other Potential Causes:
* Throttle Position Sensor (TPS): This sensor tells the computer the throttle position. A faulty TPS provides inaccurate data, leading to poor fuel delivery and stalling.
* Mass Air Flow Sensor (MAF): Measures the amount of air entering the engine. A faulty MAF sensor can cause the computer to provide incorrect fuel mixture, causing stalling.
* Vacuum Leaks: Leaks in the vacuum system can disrupt the engine's operation, leading to erratic performance and stalling.
* Transmission Issues (Less Likely but Possible): While less likely to directly cause stalling *during* acceleration, transmission problems could contribute if the engine is starved of power due to slipping or other transmission malfunctions. However, this would likely manifest in other symptoms as well.
Troubleshooting Steps:
1. Check for error codes: A scan tool can read diagnostic trouble codes (DTCs) stored in the car's computer, providing clues about the problem. This is the most efficient first step.
2. Visual Inspection: Check all visible components mentioned above for obvious signs of damage or wear.
3. Listen for unusual noises: Pay attention to any unusual sounds coming from the engine compartment.
4. Test fuel pressure: A fuel pressure gauge can help determine if the fuel system is delivering sufficient pressure.
5. Check vacuum lines: Inspect vacuum lines for cracks or disconnections.
Important Note: Without a proper diagnostic scan, pinpointing the exact cause is difficult. Taking your Buick to a qualified mechanic is highly recommended, especially for fuel system and ignition system issues, as some components require specialized tools and knowledge for accurate diagnosis and repair. Attempting some of these repairs without experience could potentially damage other components.
