* Transmission overheating: This is a strong possibility. After extended running, the automatic transmission fluid (ATF) can overheat. Overheated ATF loses its viscosity, leading to slippage, rough shifting, and the jerky ride you describe. Check your ATF level (when cool) and condition. Dark, burnt smelling ATF is a bad sign. A transmission cooler might be necessary, especially if you frequently tow or drive in hot conditions.
* Cooling system issues: While less likely to directly cause the jerking, an overheating engine can affect various systems. If the engine is overheating, the computer may be trying to compensate, leading to erratic behavior. Check your coolant level, look for leaks, and ensure the radiator fan is working properly. A clogged radiator or failing water pump could be at play.
* Fuel delivery problems: Heat can affect fuel pump performance. A failing fuel pump may struggle to keep up with demand, leading to fuel starvation, especially when the engine is hot. This can cause rough running and hesitation.
* Ignition system issues: While less common as a heat-related problem, worn spark plug wires or a failing ignition coil can cause misfires, which worsen as components heat up. This would also lead to rough running.
* Throttle position sensor (TPS) or mass airflow sensor (MAF) issues: These sensors are crucial for the engine's fuel/air mixture. If they're failing or malfunctioning due to heat, it can lead to inconsistent performance and jerky operation.
* Oxygen sensor (O2 sensor): A faulty O2 sensor, especially a heated one, can affect the fuel mixture, leading to rough running, especially at higher temperatures.
Troubleshooting Steps:
1. Check all fluids: ATF, coolant, engine oil. Note levels and condition.
2. Inspect hoses and belts: Look for leaks, cracks, or fraying.
3. Listen for unusual noises: Noises from the transmission or engine could pinpoint a specific problem.
4. Check the radiator fan: Ensure it's coming on when the engine reaches operating temperature.
5. Obtain diagnostic codes: Use an OBD-II scanner to read any trouble codes stored by the engine's computer. This can provide valuable clues.
Important Considerations:
* Safety first: If the engine is overheating, do not continue driving. This can cause serious engine damage.
* Professional help: If you're not comfortable performing these checks yourself, take your Dakota to a qualified mechanic for diagnosis and repair. The problem could be something simple, or it could require more extensive repairs.
The jerking behavior after prolonged running strongly suggests a heat-related issue. Start by checking the transmission fluid and cooling system. Getting diagnostic codes from an OBD-II scanner will be very helpful.
