ok so i plugged in the odb2 in at work today and came up with 7 different codes it said cylinder 2,4,6,8 miss fire o2 sensor 1 and 2 and o2 sensor main relay now i was under the impression that my car needed 89octane gas but i found out that it needs 93octane. is it possible that i damaged something or if i start putting 93 octane will the codes clear up? i have a 2002 disco 2 with 96k miles

 

No switching gas will not clear things out.
You need a tune up, plugs and wires.
That will take care of your mis fire codes and your O2 codes as well.
Start running 93 octane and use nothing less than 91 octane.
www.atlanticbritish.com, make sure that you use ONLY the Magnecor plug wires, if you use anything else you will be doing it again in a month.

 

Felipe,
How many miles on your truck?
Low octance can with time cause you some grief but as already mentioned, if you are at 60,000 miles or more it is time for a major service.