Fuel System:
* Fuel pump: A failing fuel pump might not deliver enough fuel to the engine, leading to power loss and stalling. This is a common culprit.
* Fuel filter: A clogged fuel filter restricts fuel flow, causing similar symptoms.
* Fuel injectors: Clogged or failing injectors can prevent proper fuel delivery to the engine cylinders.
* Fuel pressure regulator: A malfunctioning regulator can cause incorrect fuel pressure, leading to poor performance or stalling.
Ignition System:
* Crankshaft position sensor (CKP): This sensor tells the engine's computer the position of the crankshaft. A faulty sensor will prevent proper ignition timing, resulting in power loss and stalling.
* Cam position sensor (CMP): Similar to the CKP sensor, a faulty CMP sensor will disrupt ignition timing.
* Ignition coil(s): A failing ignition coil will prevent one or more cylinders from firing, leading to reduced power and potentially stalling.
* Spark plugs and wires: Worn or damaged spark plugs or wires can prevent a proper spark, leading to misfires and power loss.
* Ignition switch: A faulty ignition switch might not provide sufficient power to the ignition system.
Other Potential Causes:
* Mass airflow sensor (MAF): A faulty MAF sensor provides inaccurate air flow readings to the engine's computer, leading to a lean or rich fuel mixture, causing poor performance and stalling.
* Throttle position sensor (TPS): A faulty TPS provides inaccurate throttle position data to the engine computer.
* Vacuum leaks: Leaks in the intake manifold or vacuum lines can cause erratic engine operation and stalling.
* Alternator: A failing alternator can't charge the battery, eventually leading to the engine dying.
* Battery: A weak or dead battery can prevent the engine from starting or running consistently.
* Computer/ECM problems: A failing engine control module (ECM) can cause a wide range of problems, including power loss and stalling.
* Transmission issues: While less likely to cause a complete stall, transmission problems could contribute to power loss.
Troubleshooting Steps:
To diagnose the problem, you might consider:
* Check the engine codes: Use an OBD-II scanner to read any diagnostic trouble codes (DTCs) stored in the engine's computer. These codes can provide valuable clues about the problem.
* Inspect the fuel system: Check the fuel pressure, visually inspect the fuel filter, and listen for the fuel pump's operation.
* Check the battery and alternator: Test the battery voltage and have the alternator tested at an auto parts store.
* Visual inspection: Look for any obvious signs of damage, such as loose wires, vacuum leaks, or broken parts.
Because there are so many potential causes, it's recommended to take your Suburban to a qualified mechanic for proper diagnosis and repair. Trying to fix this without proper tools and knowledge could lead to further damage or injury.
