My wifes Mustang V6 was running just a little rough at about 60-70 mph, in what I think was about 3rd gear (auto) and about 2200 rpm. Well, i thought a new set of plugs may help. It now runs horrible. Very rough, check engine light is blinking constantly. What could it be? I have never experienced a dramatically worsened condition from replacing plugs.
Nov 23, 2009 at 9:18 PM
