2000 discovery II, 135K, all of sudden rough idle, I ran low on gas and the SES light comes on I keep a OBD II in the glovebox so I come back with p300, p303, p1300.
I clear codes put 92 octane and Lucas injector lube and clean, in her keep getting SES codes p300, with random P300 2-4 returns,:confused clear them and she is running ok still a little roughness on acceleration but once leveled out smooth sailing can anyone tell me what is going on or what to investigate?

I clear codes put 92 octane and Lucas injector lube and clean, in her keep getting SES codes p300, with random P300 2-4 returns,:confused clear them and she is running ok still a little roughness on acceleration but once leveled out smooth sailing can anyone tell me what is going on or what to investigate?