[srv1]

this is true, but you have to know how to read an O2 sensors "real time". it should toggle from .5v above and below rapidly. highest should be about 1.0v meaning rich side. .01 is lean. your 87 doesnt have a data stream. Fords used Breakout boxes. meaning you cant get sensor data unless you backprobe the circuit or use and expensive breakout box. your year only throws out codes.