1985 Subaru Wagon

Could be caused by one of the following below

Oxygen sensor.
Catalytic converter.
Fuel injectors dirty/sticking.
Mass airflow sensor/Airflow meter.
Throttle position sensor.
Crankshaft position sensor
Knock sensor
Manifold absolute pressure sensor.
EGR Valve
Fuel pressure regulator leaking or defective fuel pump.
False air leakage.
Fuel contamination.
Foul/defective spark plugs.
Open spark plug wires.
Ignition coil/Coil packs defective.
Incorrect ignition timing.
Cap and rotor.

Note:If it doesn't apply disregard it

Thanks for your reply....will take a look at the things you suggested that it might be and one by one do some eliminations. Again Thank you.

I am still trying to figure out where the fuel pump is an how to replace it...So if you know would love to have the information. Thanks again