* Fuel Filter: A clogged fuel filter will restrict fuel flow, even with a new pump. This is a relatively cheap and easy part to replace. It's often recommended to replace the fuel filter whenever you replace the fuel pump.
* Fuel Pressure Regulator: This regulator controls the fuel pressure in the system. A faulty regulator could cause low fuel pressure, leading to the engine stalling.
* Pick-up Tube in the Tank: The fuel pump's pick-up tube may be clogged or damaged, preventing it from drawing fuel from the tank. This often requires dropping the fuel tank to access and check/repair.
* Wiring/Electrical Issues: Check the wiring to the fuel pump for any damage, shorts, or loose connections. A faulty fuel pump relay or other electrical component can also cause this issue.
* Fuel Injectors: Clogged or faulty fuel injectors can prevent fuel from reaching the engine, even if there is sufficient pressure.
* Ignition System: While less likely to cause symptoms *exactly* like running out of gas, a weak ignition system (spark plugs, wires, coil) could cause the engine to die under load, giving a similar impression.
* Crankshaft Position Sensor (CKP Sensor): A faulty CKP sensor won't allow the engine to receive the signal it needs to ignite the fuel, even if fuel is being delivered.
Troubleshooting Steps:
1. Check the fuel filter: Replace it even if it looks okay.
2. Check fuel pressure: You'll need a fuel pressure gauge to measure the pressure at the fuel rail. This will tell you if your fuel pump is delivering adequate pressure. (This is the most crucial step)
3. Inspect the fuel pump wiring and relay: Look for any obvious damage or corrosion.
4. Check for error codes: Use an OBD-I scanner (for your 1990 model year) to see if any trouble codes are stored in the car's computer.
If you're not comfortable working on your car's fuel system yourself, it's best to take it to a qualified mechanic. Working with fuel systems involves flammable materials, so safety is paramount.
