My 90 lesabre just got a engine swap and it sputters at start. Youll turn it on and it will sputter and shut off with the check engine light on. If i push the acceleration it usually will drive, is it the spark plug cam sensor or what?

Or what. Get the code.

Just got an engine swap . . .

. . . with a new engine or a used engine?

. . . by a professional mechanic or something else?

I just got the check engine light fixed and the sputtering issue (replaced cam sensor). However now i just found out the ac and heat wont blow out of the main vents in the car only the vents on the top of the dash. What is wrong? Anyone else have this issue?

Common issue.

Vacuum leak somewhere, or a vacuum line is plugged.