rb20det ecu grounding problem

[s14-240]

Hi. My rb20det(in s14) currently spun a rod bearing, and I got a replacement motor, swapped it in, and drove it arround. It was fine. Then, while driving, it spontaneously shut down. The fuel pump didn't prime, the ecu light didn't come on, but the car cranked. It just didn't start. Today, I tested the ignition switch wires on the ecu plug, and they get power. Then I tested the grounds. All worked expect for wire number 30, the sensor ground. So, I attempted to ground the wire from the ecu pin by inserting a wire into the plug at that location, and then pluging the ecu in. WITHOUT grounding the new wire, the light came on, fuel pump primes, but car doesn't start. Now, when the car is cranking, the ecu light is supposed to turn off, but it doesn't. It stays on. Then I grounded the new wire to the frame and cranked. The light blinked and the ecu made a ticking sound every time the motor completed a revolution. Still no start. So:

Question 1: why did the light come on right away, when all I did was insert an additional wire but NOT ground it?

Question 2: Why would it click when grounded but stay on when not grounded, although it must be grounded or the ecu wouldn't work? But as I sayed earlier, the wire IS NOT GROUNDED

Question 3: Where does wire 30 travel to, after leaving the ecu?

My conclusions so far is that the wire is grounding partially, but somehow not properly?

One extra thing is that two of my MAF sensor wires melted partially. Prior to running these tests, I separated the two exposed wires. They still run properly and are not accidentally grounding out. Thanks for the help.Walter