sensor at rear of head near spark plug drvr side of head

Can anyone tell me what the sensor plugged into the head near the last spark plug is? My power steering pump seized up on me on the freeway the other day and there was a fire under the hood, it burned this dark green wire, which is the only wire that connects onto this sensor. It caused the car to not be able to idle whenever i would turn the heater on. And it lost power at start of acceleration from stop lights, and would pulse when slowing down. I corrected all of this when i got a new connector and some wire and spliced it onto the unburned portion of the old wire. it runs smooth again, and i can turn on the heater. This is an 88 safari with a 4.3L automatic....I posted this on the Safari board, but got no response after a week. the reason i'm asking this question is because it still does it once a week or so, i was wondering if i may have destroyed the "sensor" in the fire. Any help would be appreciated...

The thing that you are describing sounds like the coolant temp switch that activates the warning light/gauge on the speedo cluster.

foodstamp

I thought the coolant sensor was on top of the motor. Sounds more like the knock sensor to me.