* Fuel System Issues:
* Fuel pump failure: This is a common cause of sudden engine death. The pump might have simply worn out, or there could be a problem with the fuel pump relay or fuse.
* Clogged fuel filter: A clogged filter restricts fuel flow to the engine.
* Fuel delivery problems: Issues with the fuel injectors, fuel pressure regulator, or fuel lines can also prevent fuel from reaching the engine.
* Ignition System Problems:
* Distributor cap and rotor issues (if applicable): These components can wear out, causing misfires or a complete engine shutdown. (Note: 1997 Tahoes may or may not have a distributor, depending on the engine.)
* Ignition coil failure: The coil provides the high voltage needed to ignite the fuel-air mixture. A failed coil will prevent the engine from running.
* Crankshaft Position Sensor (CKP) or Cam Position Sensor (CMP) failure: These sensors tell the engine's computer the position of the crankshaft and camshaft. A faulty sensor will prevent proper timing and engine operation.
* Ignition switch malfunction: The switch might be faulty and not sending power to the ignition system.
* Electrical Issues:
* Alternator failure: While the alternator doesn't directly stop the engine, its failure will drain the battery, eventually leading to a stall.
* Battery problems: A dead or failing battery can prevent the engine from starting or running.
* Fuses or relays: A blown fuse or faulty relay can interrupt power to crucial engine components.
* Other Potential Issues:
* Overheating: An overheating engine can cause it to shut down to prevent damage. Look for signs of overheating like steam or a high temperature gauge reading.
* Transmission problems: Severe transmission issues can cause the engine to stall.
* Computer issues (PCM): Problems with the Powertrain Control Module (PCM) can disrupt engine operation.
To diagnose the problem, you'll need to check things like the fuel pressure, fuses, battery voltage, and potentially have the vehicle scanned for diagnostic trouble codes (DTCs) using an OBD-II scanner. It's best to have a qualified mechanic diagnose and repair the issue.
