fxrolla

OK, its a 99 civic dx with a obd1 head with a 96 civic intake and exhaust manifolds on it. It also has 96 civic fuel rail,reg and injectors. Now I fixed all the stupid problems on it like the knock sensor which is wired in along with the vtec shit. Had a check engine light for a low volt o2 sensor, so I changed that and put a boush that needed to me wired in. Then I was good until a po170 and a po171 popped up. Says its running to lean in bank 1>??????? Help what do I need to do????