* Increased Electrical Demand: Accelerating puts a significant load on the engine. This means more power is needed to turn the engine, and other power-hungry accessories like the fuel pump and ignition system draw more current.
* Alternator Capacity: The alternator's job is to recharge the battery and provide power to all the electrical components while the engine is running. If the alternator is weak, old, or its output is insufficient, the increased load from acceleration can cause a voltage drop.
* A/C Compressor Sensitivity: The A/C compressor is a significant power draw. When the voltage drops below a certain threshold due to the increased load, the compressor might cycle off (stop working) to protect itself and prevent a complete electrical failure. This can manifest as the A/C simply ceasing to blow cold air.
* Other Potential Issues (less likely):
* Low Refrigerant: While less likely to be directly related to acceleration, low refrigerant can cause the compressor to cycle on and off erratically. This could be coincidentally exacerbated by the voltage drop.
* Faulty A/C Clutch: The clutch engages and disengages the compressor. A failing clutch might not be able to handle the extra strain during acceleration.
* Wiring Issues: Loose or corroded wiring in the A/C circuit could worsen the problem under load.
Troubleshooting Steps:
1. Check the Alternator: This is the most likely culprit. Have the alternator tested at an auto parts store or a mechanic. A simple voltage test while the engine is idling and then under acceleration will reveal if the voltage is dropping significantly.
2. Check the Battery: A weak battery can exacerbate the problem. Have the battery tested as well.
3. Check the A/C System: While less likely to be the primary cause, a low refrigerant charge or other A/C system problems should be ruled out.
4. Wiring Inspection: Visually inspect the wiring harness connected to the A/C compressor and related components for any damage or corrosion.
In short, the acceleration is likely causing a voltage drop due to increased electrical demand exceeding the alternator's capacity, causing the A/C compressor to shut down as a protective measure. Focus your troubleshooting efforts on the charging system first.
