Just bought a 94 Lesabre with 35k miles on it I was thrilled, but it seems time has created some problems. First off after I drove it home, and the next day when it started it had trouble getting running, the engine was revving on its own to prevent stalling. I then noticed I had an air/coolant leak from the lower intake in addition to the smoke, so I replaced the gasket. Still had smoke but no coolant leak so I took the 02 sensor out to see if catalytic converter was clogged but did not see a difference in performance.
Was still seeing smoke so I did a compression test and found the throttle body gasket was leaking so I replaced it. Still had the same problem; my father read that the whole plastic upper intake usually needs replacing so that was the last step. The car does not want to stall out anymore but I'm still seeing smoke coming from the that exhaust underneath the hood. Any help would be appreciated I just got out of a bad relationship with a Taurus and I know this is going to be a great car once this problem is solved.

The plastic UIM does not typically need to be replaced unless there is a confirmed issue with it. Most issues with the UIM are limited to the Series 2, which was 95/96 and up. There should be no exhaust leak, however if oil is dripping from the valve cover gaskets, or spraying from a transmission cooler line (both common failure points) than oil can land on the manifolds and cause a nice smoke show. If smoke is coming from under the hood, but not out of the tailpipe, then something is likely leaking on to the exhaust, which you would want to track down.

I will check those valve cover gaskets in the morning but the smoke is coming from the inside of the exhaust, out through the joints of the crossover piece and it smells more like coolant