1995 explorer electrical problem

I have a 95 Explorer with about 150000 miles on it. I just had it tuned up, and it was driving fine. Yesterday the battery light started flashing, and the batter charge meter started surging. I placed a DVM on the battery, and it shows the voltage surging from approx 14.5VDC to approx 16.5VDC. The engine seems to surge a little too. I checked this under no load conditions. I have also replaced the alternator and voltage regulator thinking that was the problem. Has anybody else seen a problem like this? Any advice would be greatly appreciated!

Its normal for the voltage to go up and down as the engine idle changes. I had a similar problem with my 92. The voltage meter was going up and down, but not with the engine idle. My problem was a blown fuse for the battery meter. On mine, it was in the fuse box under the hood. Hope this helps.