Intermittent lurching and burning smell

saab
900

#1

we have a 1990 saab 900s convertible that we love dearly. we recently had trouble with the battery not holding a charge and needing to be jumped every time we started it. thinking there might be an electrical problem somewhere, we took apart and put back together the stereo, ashtray, and roof switch areas of the dashboard and miraculously the battery issue seems resolved.



but now we occasionally experience an intermittent lurching sensation when the car is going, almost like the car stutters momentarily while driving, like the gas has been momentarily turned off. and once or twice we have turned the car off at the end of a longish (20+ minutes) drive to find that the engine is emitting a burning engine/burning rubber smell.



any ideas what this might be about? thanks in advance for any insights.