Posted by Lenny D. on July 30, 1999 at 16:20:39:
Second owner since '82, my '80 528i 5 speed is outfitted with a vacuum retard nipple on the distributor but nothing has ever been connected to it. The intake manifold nipple is fitted with a rubber cap. Is this supposed to be this way? If I connect a test hose to the dizzy and pull a vacuum the idle will slow as timing is being retarded. Does any of this have to do with the notoriously 'lumpy idle' E12s are famous for? If not, what is?
Trying to solve one of life's curiously perplexing E12 problems on an otherwise superior vehicle satisfactorily owned for almost twenty years!
Lenny D.