94 SLS occasional smoke & Pulling problem

just bought a well kept 94 seville, It on occasion will blow some smoke out the exhaust when you get on the accelerator, and it consistently (while driving at a steady fuel flow ) has a pulling sensation which is coming from the engine. Other than that it runs fine.

Only fault codes

S036
S044

please help

thanks

These two codes refer to the electronic suspension:

S036 - Electronic Level Control Compressor Short to Ground/Open

S044 - Lift or Dive Signal Fault

What color is the smoke coming out of the tailpipe ?
What do you mean by a "pulling" sensation ?

I think it is black smoke, and the Pulling sensation is like it hesitates at a constant speed ( fuel Flow ), I also have a small oil leak coming from some where and it smells like burning oil after I drive for a while.