Fuel System Issues (Even with a new fuel pump):
* Fuel pump relay: The relay might be faulty, preventing power from reaching the pump. Test the relay (easy to swap with another relay of the same amperage as a quick test) or replace it.
* Fuel filter: A clogged fuel filter can restrict fuel flow, even with a new pump. Replace the filter.
* Fuel pressure: Even with a new pump, the fuel pressure might be low. A fuel pressure gauge is needed to check this. Low pressure could be caused by a faulty fuel pressure regulator.
* Bad fuel pump installation: Double-check the fuel pump installation. A faulty connection or improper installation can render it useless.
* Wiring: Check all wiring related to the fuel pump for damage, corrosion, or loose connections. A broken wire would prevent power from reaching the pump.
* Fuel injectors: The fuel injectors might be clogged or faulty, preventing fuel from reaching the engine. They'll need to be checked or replaced.
* No fuel in the tank: Sounds obvious, but worth checking!
Ignition System Issues:
* Ignition coil: A faulty ignition coil can prevent spark.
* Spark plugs and wires: Worn or damaged spark plugs or wires will prevent proper ignition. Replace them.
* Distributor (if applicable): If your truck has a distributor, it might be malfunctioning. Check the rotor, cap, and ignition module.
* Crankshaft Position Sensor (CKP): This sensor tells the computer the engine's position, vital for ignition timing. A faulty CKP will prevent starting.
* Camshaft Position Sensor (CMP): Similar to the CKP, but for the camshaft.
* Ignition control module: This module controls the ignition system.
Troubleshooting Steps:
1. Check for fuel: The most basic step.
2. Check the fuel pump relay: This is a quick and easy check.
3. Check fuel pressure: This requires a fuel pressure gauge. If the pressure is low, you've narrowed it down to a fuel delivery problem.
4. Inspect spark plugs and wires: Look for damage or corrosion.
5. Check for spark: A simple spark tester can determine if there's spark at the plugs.
6. Consult a repair manual: A repair manual specific to your 1997 Chevy Cheyenne will provide detailed diagrams and troubleshooting steps.
If you're not comfortable performing these checks yourself, take your truck to a mechanic. They have the tools and experience to diagnose the problem accurately. Providing more information about what happens (e.g., does the engine crank slowly or quickly? Is there any unusual noise? Does it smell like fuel?) will help in pinpointing the issue.
