When im parked downhill , My car turns off or shakes and like it wants to shut off...can someone help itsa 120k nissan sentra

Sounds like a fuel issue. Maybe a fuel line leaking and sucking air or a clogged fuel filter. Faulty fuel pump. Have your fuel pressure checked. Look for gas leaks. Park downhill, turn car off then being very quite turn switch on but not start position, listen for electric fuel pump making noises.

2009 Sentra: I had the same problem as many Sentra owners had. Started car and when put in drive or reverse it would spit and sputter and eventually stall. This got worse over about a six month time period. Changed all kind of things. Eventually found the 4 inch plastic intake hose near the MAF sensor had two splits in it. I couldn't see them until I physically moved it. Everytime the engine would torque in either direction they would open up and the car would run extremely rough or stall. replaced the intake hose and car runs like new! Hope this helps some one.

Anthony, did you ever get this figured out? Im seeing something similar.