First thing I'd do is check the TPS and MAF. Second on my list would be optical dizzy (works same as DSM CAS) and engine crank/cam timing. A DSM CAS being 180 out does this exact same problem as you are describing.

Kane

89 Conquest - 2.4 DOHC <--Thats right DOHC Turbo and MPI.
87 Starion flatsider - under restoration
87 Conquest - Saved from the crusher
86 Conquest - Another crusher rescue
88 Conquest - Previous owner abandoned project
87 Raider - under construction

86 Conquest - DD