First off, welcome to the board! Glad to see another VX owner here.
The info for checking the O2 with the DVM/DMM can be found
HERE. The wiring diagrams show that D14 is an orange with blue stripe and D16 is a blue with green stripe wire. These wires are located on the far right connector once the ecu is orientated like the picture in the post.
And yes, it does sound like an O2 problem.
And your best bet for L1H1 O2 sensors (the ones the VX uses) are on Ebay. The $190 +shipping is a great price for them these days.
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