Misfiring

Hi and thanks for using 2CarPros.com.

The first thing we need to identify are trouble codes. Here is a link that shows how to retrieve GM OBD1 trouble codes. Also, I need you to check fuel pump pressure to confirm it is within the manufacturer's specs. Do this and let me know what you find.

https://www.2carpros.com/articles/how-to-check-fuel-system-pressure-and-regulator

Here are the manufacturer's specs for fuel pressure:

FUEL PRESSURE
1. Ignition "OFF" for 10 Seconds.
2. With ignition "ON," engine "OFF" and fuel pump running, pressure should be 284-325 kPa (41-47 psi).
For additional fuel pressure testing procedures, See: A L L Diagnostic Trouble Codes ( DTC ) > Related Tests, Information and Procedures > A - E Charts & Related Test Procedures
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Follow these directions for retrieving diagnostic trouble codes.

https://www.2carpros.com/articles/buick-cadillac-chevy-gmc-oldsmobile-pontiac-gm-1983-1995-obd1-code-definitions-and-retrieval-method

Let me know what you find.

Take care,
Joe