my 97 ranger [4.o] [auto trans] has been missing/surging for months. i replaced plugs,wires air and fuel filters, mass air, thermastast i never had any codes, it does this at all speeds some days it acts worse. it starts ok ands idles fine ,would the coolant sensor [the one with two wires] would that cause this problem any ideals would sure help thanks.

 

I've seen bad temp sensors cause idle speed and richness issues. But never a miss.

I gotta think it's ignition related. Maybe a crank position sensor, cam sensor, or possibly a coil.

Rich

 

when you say coil, do you the oil pack thanks

 

Do what? The coil pac sits on top of the motor and all 6 plug wires go to it.
If you replace it.. try one of those screamin demon ones.

Rich