How did you know the coolant sensor had gone bad? Was the car throwing a code? So, if I short the two pins on the diagnostic connector to read any codes, I can hear them rapid-firing from under the hood. If I just key on, they're not going. Not sure if they're supposed to be moving when I'm just in key-on, or only when the car is running (when you'd not really be able to hear them anyway). Distributor is original, so that should be good. O2 is old, but I have a new engine-side pigtail so I can go ahead and get a true extension harness and install the new O2 I have for the car.