Lots of good info. Where can I find a entire mono valve? I can find many sites for the plunger replacement but not the entire unit. However before going out and buying more parts will try a few of the thing suggested.

Many thanks

P.S. I am the 3 owner on this great car. Bought it with 192,000 and I now have 410,000. It has served me very well and plan on 500,000 plus. Just had to mention this!