* Faulty Alternator: This is the most likely culprit. The alternator recharges the battery while the engine is running. If it's failing, the battery may not be receiving sufficient charge, leading to the car dying when the demand is high (like running the AC, headlights, or other accessories). The jump start might have temporarily masked this issue, but now the problem is more apparent.
* Faulty Battery: Even a new battery can be faulty. A manufacturing defect or damage during shipping/installation could cause intermittent power issues. The jump start might have temporarily boosted it, but it's now showing its true state.
* Loose or Corroded Battery Terminal Connections: Improper connection during the jump start (or pre-existing loose connections) could have exacerbated a problem. Poor connections prevent the battery from properly charging and discharging.
* Electrical System Problem: There might be a short circuit or other fault in the car's electrical system. The jump start could have stressed a weak component, causing it to fail. This is less likely, but possible.
* Sensor Issues: A faulty sensor (like the crankshaft position sensor or camshaft position sensor) could cause the engine to cut out intermittently. While unlikely directly related to the jump start, a pre-existing fault might now be manifesting.
* Software Glitch (Less Likely): In modern cars with complex computer systems, a software glitch could cause intermittent power issues. This is less likely to be directly caused by a jump start but is possible in extreme cases.
What to do:
1. Check the battery terminals: Ensure they are clean, tight, and corrosion-free.
2. Have the alternator tested: This is the most important step. A mechanic can easily test the alternator's output.
3. Have the battery tested: Even a new battery can be defective. A load test will determine its condition.
4. Get a professional diagnosis: If the above checks don't reveal the problem, take the car to a mechanic for a thorough inspection of the electrical system. They have diagnostic tools that can pinpoint the issue more accurately.
Don't continue driving the car if it's randomly shutting off. This is dangerous and could lead to further damage.
