I forgot to ask: Are you using a driving style that would net a higher than normal mpg? or are you just driving the car like a regular car and shifting when the light tells you?
Given the fact that the FE of the VX is greatly affected by temps could be a factor at this time of year. But if you are driving the car without much FE technique the car is actually getting the mileage it should be.
The other things to look at now:
De-carbonizing the motor/intake manifold and EGR system.
Checking for proper gap and spark plug type (all listed in the VX lean burn monitor post in General Tech) VX Lean Burn Monitor
check condition of brake components for dragging
check condition of CV joints
Check air pressure in tires
ive been driving without flooring it anywhere, i shift around 15-1600rpm, usually well before the light tells me to shift, i use the highest gear possible when city driving to keep the rpms there lowest. i figured doing this should net higher MPG
one thing i was wondering, is a 2000-2200 rpm idle at 60mph in 5th gear normal? seems my 95 civic EX is about the same rpm at the same speed
today, i did the pulse and glide driving all day, i put 150 miles on it, and at the end of the day filled up to get 52.3 mpg. does everyone have to use pulse and glide to get what the EPA recomends with these cars? seems like alot of work to reach only what the EPA says the car should get
also, ive already "seafoamed" the motor and manifold, it was dirty but didnt make a difference
replaced and gapped all plugs (the proper VX plugs)
not sure how I check the CV joints? there is a slight pull at speed, i need to figure out what that is
i got excited when i saw 52mpg today with the pulse/glide technique, i think i aggrivated quite a few drivers on the road who were following me, they probably thought i was drunk haha
i need to check the timing as well, seems sometimes going uphill, it feels like there is no power, or at least even less power then there usually is