I have an issue with my sti..

I cant keep the motor in tune.. I think the plug was going out.. when I changed it... the motor ran hot. not over 250. but the motor really is acting up. I took the motor out..

Anyone have tips for tuning.

I cant keep the thing running at a decent idle... I have to run it fast to keep it alive.

I am going to break in my new motor.. I just dont want the same issuses

Thanks

If I need to replace anything. what do you think it would be.? It seems to have good compression... its still fast but the motor seems to be slow if the temp is not at aleast 220.