This weekend, I found my temp gauge was going ABOVE RED when starting up. On my way to school today , I pulled over, touched the engine and it didn't seem...abnormal, then got back on the road, and the needle went back down.

Here's what I've tested so far...

Thermostat:
-Tested Ok

Sensor B (Towards front, #18 on picture below)
-Could not test acuratly (can't get water above 215*F, tried torch near bottom) DID turn on...so not suspecting it.
-When plug jumped:
=Car off: Turns 1 fan on
=Car on: Turns 0 fans on

Sensor A (On thermostat housing, #17 on picture below)
-Tested Ok
-When jumped
=Car off: Turns 0 fans on
=Car on: Turns 2 fans on



What could be causing this? What sensor does the needle get it's reading off of?

and this is for a 1994 accord lx (f22b2, auto)