Ok, so i have a 2004 honda civic EX 1.7L automatic, with about 144,444miles on it. my o2 sensor (air to fuel) sensor has been out for aproximitly 6 months, the only reason i have not changed it was because it was a $150 sensor. now, my car smells like its running rich now and it shakes when i start it, but the shaking goes away when you moving, its only at idle. i just ran engine diagnostics and it says i have a misfire on cylinder 1. i just had my sparkpulgs replaced about 30,000 miles ago, so i dont think its that, my question is, could the o2 sensor have caused this