I just bought a 95 VX a few weeks ago and just started driving in as a DD. I have a CEL (code 48 - LAF) coming up once I start driving the car for less than a mile at times and not until 6-7 miles at other times. When cruising at 50+ mph I can feel the engine delivering power then holding back, going back and forth like this ever so slightly when the CEL is NOT on. Once the CEL goes on this issue goes away, and the car cruises fine with no slight hesitation at all like it was. I am assuming this is a sign of the 02 sensor that has gone bad.
I have done a full tune up on the car with all the usual things noted on this website. Just did 39 mpg on the first fill up, but it was only 120 miles just to see what it was doing.
you're getting crap mpg when you are driving with the CEL on. Until you fix it, you should take that cue to turn your engine off and glide for a bit, then bump start and repeat when the CEL comes back on. To get better gas mileage, avoid driving with the CEL on. See how long it takes to come back on if you turn car off and then bump start it after it comes on. But, yeah, I concur-- a new o2 sensor will fix the inability to cruise at a constant speed (I had the same problem--you can read about it in another recent thread I just posted in an hour so ago)