I have a 1991, convertible, 2.3 stock engine. My car runs very rough when first starting and during acceleration. After a few minutes of driving the check engine
light will come on and it starts running a lot better but still with some hesitation during acceleration. I have replaced the plugs, wires, both coils, Idle air control valve, throttle position sensor, fuel pump, fuel filter, battery, done an air induction cleaning, and run cleaner thru my gas. I use Shell premium plus gas. The only things left I can think of are the mass air flow sensor, although I did clean it and the engine will run differently when unplugging it while at idle, the fuel injectors, and PCM. Any suggestions??