can any one hel;p me to figgure out whats wrong with my 240 sx and how I can fix it

I Love My Car, But Don’t Know What Wrong. The Car Runs Great After It Warms Up Alot It Has 400,000+ Kl On It. After I Drive It For A While And Turn It Off Fo 20 Min Or More It Seems To Kind Chug Un till I Rev It And Rev It Then It Goes Gr8 But If I Just Start It And Try To Drive It Almost Wants To Stall Out . It Is A Automatic And The Transmishoin Seems Good. Its Also Acts Up After The Car Wash Like There Is Water In The Engine Or Something??? Also When I First Start It From Cold The Lights And Fan Are Very Week Un till Again I Rev The Hell Out Of The Engine> I Did Some Work Ont The Fuil Injector Plugs A While Ago Because The Engine Was Shaking Like Crazy And That Solved The Problem But I Don’t Know What To Do About The Hot Starts I Allread Killed One Starter!! And My Heat Wont Stay Hot As Well The Heat Gauge Says Its At Around 50% And Then Once I Run The Heat In The Car It Dropss To 0% And The Heat Doesn’t Come Hot Un till I’ve Highway Driven It For 4 Hrs Or More But It Still Drops As It Is Used!1 I Don’t Know Much About Cars As This Is My First. I Also Am Very Limited To $ To Invest In This Car Any Cheep Suggestions On What Might Fix These Major Problems Would Be Very Help Full …

why 2 posts ???