problem with '89 9000S
 

ok...here's the problem:
I'm driving and periodically the engine suddenly stops responding to the gas pedal. As a result the engine rpm's start going down until they drop down to 0 and the engine stops. Then I have to restart the car. Sometimes the engine will suddenly stall at a stop light. Could it be an ignition or a fuel problem? Thx, trying to keep the car out of the dealership since a repair there will probably cost more than the car itself. BTW, the car has 151,000 miles on it.