97 Cav 2.2 stumble - rough idle

I have a '97 2.2 Cav. It has 184K miles, auto trans. The problem is intermittent and the check engine light is not illuminated. The main problem is a stumble off idle when accelerating up to about 1200 RPM. From that point on, it runs great. Also intermittent rough idle.

Various codes have appeared, but been rectified.
Parts changed thus far: injectors, fuel filter, coil packs, throttle position sensor. All have been changed to correct "check engine" light.
I suspected bad gas, but alcohol additive did not help.

Any suggestions would be greatly appreciated.

Thanks,

would suggest putting a good scanner on it if possible. look at misfir counters(may misfire without setting codes), and so on to try and narrow it down.

Check for vacuum leaks and with those miles you would really benefit from some auto-rx. My 98 Transport with 172K miles was transformed after using auto-rx. No more rough idle. :)
www.auto-rx.com