What Happened
1. You drove ~2,300 miles continuously, so the car was running fine.
2. Starter failed ~300 miles from destination, and the car was towed.
3. Car sat for two weeks after the tow.
4. You replaced the starter.
5. Car cranks, fuel has been primed, glow plugs get red-hot, but it still won’t start.
6. You see white smoke from the oil filler cap when cranking — meaning fuel is entering cylinders but not igniting.
7. Jumping from a newer car doesn’t help start it.

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Key Clues
• Glow plugs are working → not the culprit.
• Fuel is reaching injectors → pump and shutoff valve are likely fine.
• White smoke → fuel present but not igniting.
• Sitting + old starter + battery = possible low cranking speed, preventing cylinders from heating enough for ignition.

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Most Likely Causes
1. Weak cranking / low RPM (most likely)
• Starter may be old or battery too weak even with jump.
2. Tiny air in fuel system
• Could prevent full fuel pressure under cranking.
3. Less likely
• Compression too low (unlikely after running 2,300 miles)
• Timing slipped (rare unless chain/pump loosened)