1. Safety First: Disconnect the negative battery terminal before starting any electrical work.
2. Check the Fuel Pump Relay:
* Locate the relay: Consult your owner's manual or a repair manual for the exact location of the fuel pump relay. It's often in the underhood fuse box or a separate relay center.
* Visually inspect: Check the relay for any obvious signs of damage (burnt contacts, etc.).
* Swap the relay: If possible, swap the fuel pump relay with a known good relay of the same amperage and type (usually a 30 amp relay). If the problem goes away, the original relay is faulty. If it persists, the problem is elsewhere.
3. Check the Fuel Pump Fuse:
* Locate the fuse: Again, your owner's manual or a repair manual will show the fuse location and amperage.
* Inspect the fuse: Check for a blown fuse (a broken filament inside). Replace with a fuse of the same amperage if blown.
4. Check for Power at the Fuel Pump:
* Locate the fuel pump wiring connector: This is usually near the fuel tank. You might need to access it from under the car.
* Use a multimeter: With the ignition switched ON (but not cranking the engine), test for power at the fuel pump connector using a multimeter. You should have battery voltage (12V) on one wire. If there's no power, the problem is upstream of the pump.
5. Check the Inertia Switch:
* Locate the inertia switch: This is a safety device that cuts power to the fuel pump in a collision. It's usually found under the dash or in the engine compartment.
* Reset the switch: Push the button on the inertia switch to reset it. Sometimes it trips unexpectedly.
6. Check the Fuel Pump Wiring:
* Inspect wiring for damage: Look carefully at the wiring harness running to the fuel pump for any cuts, abrasions, or corrosion. Repair or replace damaged wiring.
* Check for continuity: Use a multimeter to check for continuity in the wiring from the fuel pump relay to the fuel pump connector.
7. Check the Fuel Pump itself (least likely, but possible):
* This is more involved: It requires dropping the fuel tank, which is a significant job. It's best to try the above steps first.
If you've checked all these and still have no power to the fuel pump:
* Professional Help: It's time to consult a qualified mechanic. The problem could be a faulty PCM (Powertrain Control Module), a wiring problem within the vehicle's harness, or a more complex electrical issue.
Remember to consult a repair manual specific to your 1996 Oldsmobile 88 for detailed diagrams and instructions. Improperly working on your car's fuel system can be dangerous. If you are not comfortable performing these checks, have a qualified mechanic diagnose and repair the problem.
