Engine Mechanical problem
1995 Buick Riviera 6 cyl Two Wheel Drive Automatic

I have a 1995 Buick Riviera that I just picked up the thing starts just fine BUT it die's right after that .. I can keep it running by pumping the gas Just bearly When i bought this thing the person said they had to charge the key because lock broke in the column.. [They put a new lock in]they say this is when the car started to do this and they put new pick up's on the motor [timeing ext] the car will run if i fan the petal and rive up but wont stay running when i stop with the gas..Or helping it run.. Can the int thief have some thing to do with this in some way ??? why i ask is they were told to have the key flashed for the car I have read some of your Question/answer here.. One of them said to look in to the fuel out or in put I have called a lock smith and they said they have heard of this [Int thief] doing this.. Before i put any money in to it I want to be heading in right place. Iam going check the fuel pressure as it say's to do.