I have 99 blazer with random miss fire x3 and catalytic convertwe code and after I wash it emissions code's after I get on it the check engine light flashes until it drops under 25 and when warmed up it runs like cap but when it's been sitting for 5 hours runs great until operating temp I got the blazer for free I have been told that plugs and wires and Cap and rotor will fix most of the problems along with a new cat and it says I need a new o2 sensor I'll get the codes here in a bit just really confused any help would be great