I have an 89 mustang 5.0. Ive been having misfire issues and cant figure it out. It feels like its always misfirring but I have noticed that depending on the weather is how it will run. Usually in decent, not too cold or too hot weather it runs smooth and doesnt feel like it lacks power but other times it runs very rough and lacks alot of power. I jumped for codes with a test light and i used a scanner and i did not get any flashes. Abyone have any idea? Plugs are new, wires are new. And if any of you have any idea on why my starter still stays engaged even with the key out of the ignition, It would really help. New starter, new solenoid. Im hoping i didnt get myself into a big mess buying this car. Thank you