* Fuel pump: A weak fuel pump might provide enough fuel for idling but struggle to keep up when you demand more fuel by accelerating. The engine dies because it's starved for fuel.
* Fuel filter: A clogged fuel filter will restrict fuel flow, exhibiting similar symptoms to a weak fuel pump.
* Throttle Position Sensor (TPS): (If fuel injected) The TPS tells the computer how much fuel to inject. A faulty TPS might give inaccurate readings, leading to insufficient fuel when you accelerate and subsequently stalling.
* Crankshaft Position Sensor (CKP): (If fuel injected) The CKP tells the computer the engine's rotational speed and position. A malfunctioning CKP can cause erratic fuel delivery or ignition timing, leading to stalling.
* Idle Air Control Valve (IACV): (If fuel injected) The IACV regulates airflow at idle. A dirty or malfunctioning IACV can cause rough idling and stalling when you lift off the accelerator, as the engine struggles to transition.
* Vacuum Leaks: Vacuum leaks can disrupt the engine's air/fuel mixture. A significant leak could cause the engine to run poorly under load and die when the accelerator is released. This is more common in carbureted systems but can still affect fuel-injected Jeeps.
* Distributor Cap and Rotor (if applicable): On older, non-computer controlled Jeeps (or if it has a distributor), worn or damaged distributor parts can cause misfires and stalling, especially under load.
* Ignition Coil: A weak ignition coil may struggle to provide sufficient spark at higher RPMs.
Troubleshooting Steps:
1. Check for obvious issues: Look for loose vacuum hoses, disconnected wires, or anything visibly amiss under the hood.
2. Listen closely: Does the engine sputter or cough when it dies? This could indicate a fuel or ignition problem.
3. Check the fuel pressure: If you have the tools, measure the fuel pressure. Low pressure points to a fuel pump or filter issue. (This requires a fuel pressure gauge and specialized knowledge).
4. Inspect the fuel filter: A visual inspection might reveal a clogged filter. Replacement is inexpensive and relatively easy.
5. Check the spark: If you have some automotive knowledge, check if you're getting spark at the spark plugs when the engine dies.
Important Note: Without more information (e.g., type of engine, fuel injection vs. carburetor, any other symptoms) it's difficult to pinpoint the exact cause. If you're not comfortable working on your Jeep yourself, take it to a mechanic. Misdiagnosis and incorrect repairs can lead to further damage and higher repair costs.
