Tim,
The above posts have pretty well covered what the most likely things could be and grounds are really suspect in a lot of electrical problems. If you have a voltmeter and can get the car to do its thing standing still, just measure across the - & + terminals of the battery and see if the voltage varies. Mine runs around 14 volts as the RPMs go above idle and around 12-12 1/2 at idle. I have a dash mounted voltmeter that I watch all the time along with the rest of the gauges. By surging I figure you mean the actual running of the car and at higher RPM you will use more power to fire the plugs.
Ron61
Ron Widener
