99 civic ex couple d16y7.

The long term fuel trim reads in the high 6s low 7s on the highway. It goes down to 4.63 during in town driving. I've replaced the fuel filter, plugs, and ran a bottle of techron through the fuel system. Any ideas?

Also which sensors affect the fuel trim? In other cars I've driven it's a factor of coolant temp, air temp, map, and o2; same here?

Thanks.