2000 Chevrolet Monte Carlo

I have a 2000 Chevy Monte Carlo SS 3.8 L with 93,000 miles and an engine surging around 2000 rpm's when I am accelerating from about 30 mph and also at about 50 mph. I've had the car to the dealership twice--once for a cracked spark plug (all spark plugs were replaced about 20,000 miles ago when the upper intake manifold cracked) and another for a 5th cylinder coil and wire. Recently (about 5 months) the thermostat, fuel line sensor, and hazard switch were replaced. It usually will surge with or without the cruise control on.
September 15, 2007.

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