Postscript: I replaced the LAF sensor last week. I followed all my fellow posters recommendations. The old VX now runs much better than before-no Check Engine light, much smoother idle, and I'm able to get the rpm's up when slipping the clutch to get going from a standing start up hills again! There's no substitute for having the correct tools to do a job; it only took about 20 minutes to take care of this one.
Considering how much it cost for the OEM LAF sensor (even the item mentioned by djenyc, which is less than what I paid), this is not something a DIY mechanic should try to take shortcuts on. The LAF sensor on the VX is a major part of the technology that enables this model to get such outstanding gas mileage. Make sure to use proper tools and installation protocols, and the job will go smoothly.
Simplicity is the glory of expression.-Walt Whitman