1. Idle Air Control (IAC) Valve Problems: The IAC valve regulates the amount of air entering the engine at idle. A malfunctioning IAC valve can cause the engine to stall, especially when the engine load changes (like when turning the steering wheel puts extra stress on the system, then suddenly stops). A dirty or faulty IAC valve can't maintain a proper idle speed.
2. Alternator Issues: A failing alternator may not be providing sufficient charge to the battery. When turning the steering wheel, especially at low speeds or during parking maneuvers, there's increased electrical demand. If the alternator is weak, the voltage may drop too low when this extra load is removed, causing the engine to stall. This is more likely if you also experience dimming lights or other electrical problems.
3. Power Steering System Problems: While less directly related, issues within the power steering system could indirectly contribute. If there's a leak or a significant problem with the power steering pump, the extra load on the engine while turning could cause a temporary dip in power, making the engine more prone to stalling when the load is removed.
4. Vacuum Leaks: A vacuum leak can disrupt the engine's air-fuel mixture. The added stress of turning might exacerbate a small leak, leading to stalling when the stress is relieved. This is a more general engine problem that could manifest in this way.
5. Throttle Position Sensor (TPS) Problems: The TPS tells the engine control unit (ECU) the throttle's position. A faulty TPS could provide inaccurate readings, leading to improper fuel delivery and stalling, potentially triggered by the change in engine load during turning.
6. Engine Mounts: While less common, worn-out engine mounts can allow excessive engine movement. This might cause electrical connections to temporarily disconnect or strain other components, leading to stalling when the engine settles into a different position after turning.
7. Fuel Delivery Issues: Though less likely to be directly related to *just* turning, issues with the fuel pump, fuel filter, or fuel injectors could cause inconsistent fuel delivery. The extra stress of turning might briefly worsen the problem, leading to a stall when the demand decreases.
Troubleshooting Steps:
1. Check the battery and alternator: Have the battery tested for voltage and the alternator tested for charging capacity.
2. Inspect the IAC valve: It might need cleaning or replacement.
3. Check for vacuum leaks: A mechanic can use a vacuum gauge or smoke test to identify leaks.
4. Inspect the power steering system: Look for leaks or unusual noises.
5. Have the TPS tested: A mechanic can easily diagnose TPS issues.
Important Note: Without more information, it's difficult to pinpoint the exact cause. If the problem persists, it's crucial to have a qualified mechanic diagnose the issue properly to prevent further damage and ensure safe operation of your vehicle. Providing more details, such as the vehicle's make, model, and year, as well as any other related symptoms, would help in narrowing down the possibilities.
