linda kay

my 04' Silverado with 5.3L has given me more grief then good. and now she flashes the service engine light a few times just randomly, starts to run crappy like shes gonna stall then comes out of it and now drips black liquid from exhaust tip. just replaced upstream O2 sensor cuz she ran like a modified stock car. I just want to fix what's broken and not everything possible in the lineup cuz its costing me a fortune. any thoughts to help me out guys? This girl is fed up!