codes shown 45, 51 ,42 whats the probeem starting

code 42 is "intermittent code" (for the ECU presumably)

45 is Oxygen sensor (rich exhaust) 51 (what I could find PROM error [programmable read-only memory]

I'd look at battery and chassis ground as the cause of many on-board computer problems, also check the age of the battery seven years old is TOO old~