This is a Cali '85. Will try to look into the emmissions controls.

Even when warm, it tends to not want to hold a constant speed in the 40 to 70 mph range. It either wants to slow down or speed up too much on more throttle. This also shows up as surging on cruise control.

Prior to posting the original message, I did check all of the banjo bolts and cleaned considerable crud from the one on the manifold. This seemed to help some but not as much as hoped for.

I may be spoiled by our 1991 350SD but it seems like the throttle control should be a little smoother. Thanks for all of the ideas and and more that may come.

Roger