I have a 1997 Legacy Outback 2.5L that's giving me fits with a rough/low RPM idle. I'm trying to check the TPS with no success. The maintenance manual I have says to check the voltage changes while opening/closing the throttle between pins 1&3, it should vary from .5 to 4.5 VDC. I'm just getting 5VDC with no variation. I checked my sons 1998 2.5L, and it's the same, so I must be doing something wrong. Any help?