MY DEVILLE BEGIN STALING WHEN I STOP. I HAD THE CODES READ AND CHANGED THE FOLLOWING:

EGR
IDLE AIR CONTROL
MASS AIR/MAP CENSOR
BATTERY
OIL CHANGE
SPARK PLUG

BUT THE CAR STILL STALL WHEN I STOP. TOOK IT TO A MECHANIC WHO STATED THE CAR WAS LOSING OIL PRESSURE AND MAKING THE CAR SHUT DOWN. WHAT CAN I DO ABOUT THIS TO FIX THE PROBLEM?

you need to find out what the OIL PRESSURE should be for this car and try to get an oil pressure guge on it 40 - 60 psi but get the right information for you car and see if you have oil Pressure and if you do the you may have a bad oil pressure switch.

northstars do not have an oil pressure shut off....i would be looking more towards the Ignition module or crank sensors and the wiring between the 2