NISSAN ALTIMA ENGINE SYMPTOM

So, I Have A Major Oil Leak, Like So Major That It Seems Almost Like When I Put Oil In It Pours Right Back Out. I've Completed An Oil...

When It Parked It Has A Rough Idle And If You Run The Heater Or A/c It Runs Rough But If You Out It In Neutral It Will Clear Up.

Went From 31 Highway, To 18, City 22 To 15. I Replaced Plugs, Air Filter, And Master Air Flow Sensor. It Acts Like It's Missing...

Yesterday I Noticed Car Smoking Lightly Under Hood And A Weird Smell In Car After Getting Gas. I Checked The Oil Dipstick And Car Was Out Of...