Hi guys. Great site. I have gotten some great info from here in the past year, but today I decided to actually register and post.
I got my VX a little over a year ago with about 137k on it. It had been lowered dramatically (read "dropped on its nuts"), had super wide 17" rims, had a "customized" air breather, and had a non-standard exhaust (read "super loud muffler" and "no cat"). I had it raised up as close to spec as I could get it, replaced the wheels with the lightest aluminum 13s I could find, and fixed all of the exhaust leaks. Also replaced plugs, wires, dist cap & rotor, brakes, air filter, valve cover gasket, fuel filter, fuel pump, steering column, cleaned the O2 sensor, and had the stock 5spd torn apart and rebuilt with all new seals and bearings.
After some serious commuting, it now has 167k on it. For most of that time, I was getting 43 MPG pretty consistently (80% highway driving @ 65MPH). In the past month or so, I have noticed a drop to about 36-38 MPG. Where do you guys thing I should start looking for issues? I have no CELs and the car doesn't run any different than it has been. The car runs Mobile1 10w30 High Mileage.