1996 Chrysler Voyager 3.8L Engine P0300 Random Misfire: Causes and Solutions

I own a 1996 Chrysler Grand Voyager with 257,000 miles and a 3.8L engine that has been running roughly for some time. After receiving an OBD2 code indicating a faulty oxygen sensor, I replaced the sensor. However, this was followed by a P0300 random misfire code. I identified a vacuum leak, which improved overall engine performance—but the vehicle still struggles significantly during acceleration. It idles smoothly and can be revved up in park without issues. The car runs fine at cruising speeds but fails to accelerate properly. I've already replaced the spark plugs and ignition wires. When I tested the fuel injectors with a screwdriver, they all produced a consistent clicking sound—indicating possible delivery issues. However, I have not yet removed them for inspection due to the complexity of the job. My main concern is: why does the engine misfire and lose power specifically during acceleration? The issue doesn't occur at idle or steady speeds. Could there be an underlying problem with fuel delivery, ignition components, or a component that fails under load? I cleared the P0300 code after replacing the plugs, and it has not returned since. While backfiring and hesitation during acceleration persist (though less severe), I recently noticed that my console lights briefly blinked on and off while accelerating—similar to a momentary power loss. This symptom hasn't been replicated consistently, and the check engine light remains off. I've tested the EGR valve and confirmed it moves freely at 2000 RPM. A vacuum test as outlined in the Haynes manual also passed. I’ve verified coil resistance (primary and secondary) and found no issues. Could a coil still fail under high load during acceleration? Any insights on fuel pressure or volume testing would be greatly appreciated.