BUCKING CAUSED BY STUCK VACUUM ADVANCE

We have seen some issues with the vacuum advance plungers getting stuck on the Saab 900 and Saab 9000 cars causing the vehicle to buck on acceleration. What typically happens is the arm on the vacuum advance binds due to poor lubrication but releases once a certain amount of pressure is reached. The cure for this is to replace the vacuum advance or the complete distributor but a temporary fix is the pull the vacuum hose off the silver vacuum advance and squirt a small amount of WD40 or oil into the fitting where the vacuum is pulled in.