1999 nissan altima starts and runs hard for a few seconds and cuts out hard

my 99 altima died driving down the road, towed it back to the house and found that the
rotor button inside the distributor had came off do to the screw that hold's it in place
striping out. I replaced the distributor button and cap. cleaned out the air intake
manifold.   put everything back together and started up and drove it probably about 35
miles and it died again. took the air intake hose off and noticed oil in the hose. i hear
the fuel pump come on, crank it the 1st time and starts right up at a high rpm. runs
about 20 seconds and dies out with a hard jult. 2nd time turn the key wait to hear fuel
pump come on and finish, crank it, it starts up but with a low idle and dies after 15-20
seconds. same thing on the third try. i push the gas and it dies out. don't know whats
next?